WTN/Wine Advisor: Primitivo or Zinfandel?

[Robin Garr]

Primitivo or Zinfandel?

Is it Zinfandel, or is it Primitivo? Oddly, the Italian red wine we feature today is <i>both[/i], if its label is to be believed: The Italian Primitivo gets top billing, but the bottom of the label, in fair-size print, reads (in English), "From Old Vines Zinfandel."

How's that?

What we have here is a case of grape science catching up with reality, while bureaucracy lags behind.

Zinfandel, long called a "mystery grape" because it seemed to appear from nowhere in California Gold Rush days, hyped by a promoter named Agoston Haraszthy, who claimed that he had brought the rare grape to California from his native Hungary. In fact, Haraszthy certainly exaggerated his role: Zinfandel (sometimes rendered "Zinfindal," "Zierfandler" or "Zeinfindall") was well-known in the Eastern U.S. as a table grape long before Haraszthy set foot in Napa. It had turned up in a horticultural fair in Massachusetts as early as 1834.

Also, based on similarity in the grape and its leaves and the wine it made, Zinfandel for many years was thought to be a sibling of the Southern Italian Primitivo of Puglia.

It was only as recently as 2001 that modern grape sleuths, including Dr. Carole Meredith of the University of California at Davis, used DNA technology to confirm that Zinfandel and Primitivo are the identical grape, albeit different clones; and the same is true of the little-known Crljenik Kasteljanski of Croatia, which is now thought to be the original variety, exported to Italy as Primitivo and to the U.S. as Zinfandel.

Based on this evidence, the European Union moved quickly to permit Italian producers to use either "Primitivo" or "Zinfandel" (or, as in the case of today's wine, both) to label wines made from either grape. The move makes great sense for Italy, as Zinfandel is immensely popular in the U.S. and more likely to sell wine exports than the relatively unfamiliar Primitivo.

U.S. regulators, on the other hand, have been slower to approve legal changes. The name Primitivo is now permitted for U.S. wineries (such as Rabbit Ridge) making wine from the Primitivo clone; but in contrast with European rules, American wineries may not use the names Primitivo and Zinfandel as synonyms. A proposal to allow this has been on the books since 2002 but has not been acted upon, reportedly because of opposition by Zinfandel producers who aren't excited about the possibility of competition.

Meanwhile, because the U.S. has signed off on the European labeling laws, this results in a curious situation in which European wineries may call Primitivo "Zinfandel" in U.S. sales, but American wineries may not.

Frankly, and probably more because of differences in wine-making styles than in fruit or <i>terroir[/i], I have rarely found Primitivo and Zinfandel all that similar. There's often a berry-like character in both, but differences typically fall acros the usual Old World-New World lines, with most Zins landing on the big fruit, high-alcohol side, while Primitivo tends to lower alcohol and hints of earth, plus a whack of oak if the producer wants to impress the critics.

Today's wine hits a pleasant happy medium. Frankly, despite the "Z word" on the label, I don't know that I would have called it as a Zin or a Primitivo in a blind tasting. But I like its balanced presentation of berrylike fruit and subtle earth and its appropriate but not over-the-top 13 percent alcohol, all of which make it a better food wine than many a "monster-style" Zin.

Villa Brondello 2005 Primitivo Puglia "From Old Vines Zinfandel" ($11)

Inky blackish-purple with a thin violet edge. Aromas reminiscent of Zinfandel but throttled back, black raspberries and a more winey hint of Chambord raspberry liqueur with a faint earthy back note. Black fruit flavor held up with crisp acidity and marked tannins; 13 percent alcohol makes it relatively lightweight compared with its New World cousins, but I like it the better for that. U.S. importer: Scoperta Importing Co. Inc., Cleveland Heights, Ohio. (April 5, 2008)

FOOD MATCH: A natural with a simple dinner of spaghetti and meatballs.

VALUE: Hard to beat at just over $10 in today's economy.

WHEN TO DRINK: The good combination of fruit, acidity and tannins suggests at least modest aging potential, but it's really meant to drink up, particularly since the track record for synthetic corks in cellaring remains doubtful.

FIND THIS WINE ONLINE:
Check prices and find limited vendors for Villa Brondello's wines on Wine-Searcher.com:
http://www.wine-searcher.com/find/Brond ... g_site=WLP

U.S. readers may be able to get more information about local distributors from the importing company, Scoperta, in Cleveland Heights, Ohio.
http://www.tmarchettico.com/contact.html

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Some interesting features of the primitivo clone include looser bunches, (which lowers susceptibility to rot) and much less propensity to raisin, as well as somewhat higher levels of acidity at ripeness. George Hendry had adjacent blocks of Zin and Primitivo on identical soil, vinified the wines identically, and they tasted markedly different out of barrel in January following harvest (this was six or seven years ago). I preferred the Primitivo, but agreed that, though it presented some strong familial resemblance, it "didn't quite taste like Zinfandel." But it was damn good, so who cares?

[Robin Garr]

Some interesting features of the primitivo clone include looser bunches, (which lowers susceptibility to rot) and much less propensity to raisin, as well as somewhat higher levels of acidity at ripeness. George Hendry had adjacent blocks of Zin and Primitivo on identical soil, vinified the wines identically, and they tasted markedly different out of barrel in January following harvest (this was six or seven years ago). I preferred the Primitivo, but agreed that, though it presented some strong familial resemblance, it "didn't quite taste like Zinfandel." But it was damn good, so who cares?

Thanks, Steve ... Erich Russell tells a very similar story of his Primitivo and Zin, and they do seem very different from bottle, although I have a hard time parsing fruit from oak in that instance, as I recall. It's good oak, though ...

Frankly, and probably more because of differences in wine-making styles than in fruit or terroir, I have rarely found Primitivo and Zinfandel all that similar. There's often a berry-like character in both, but differences typically fall across the usual Old World-New World lines, with most Zins landing on the big fruit, high-alcohol side, while Primitivo tends to lower alcohol and hints of earth, plus a whack of oak if the producer wants to impress the critics.

Look at my last name and a map of Apulia and you should quickly see where the name originated. Although this is no good reason for it, it is still a reason for my somewhat heightened interest in Primitivo. (Maybe I just wanted an excuse for drinking more wine!?) In any event, I have to say that I agree wholeheartedly with Robin's estimate of the situation. Rarely has any Primitivo I've tried been "unmistakenly zinfandelish," perhaps not unlike the Patty Duke Show and her identical cousins.

It was only as recently as 2001 that modern grape sleuths, including Dr. Carole Meredith of the University of California at Davis, used DNA technology to confirm that Zinfandel and Primitivo are the identical grape, albeit different clones; and the same is true of the little-known Crljenik Kasteljanski of Croatia, which is now thought to be the original variety, exported to Italy as Primitivo and to the U.S. as Zinfandel.

We should not forget though, that when it comes to grapes DNA is not everything: remember that grapes as different as Pinot Gris, Pinot Blanc and Pinot Noir are indistinguishable when looking at their DNA!

Greetings / Fredrik L

[[/quote]We should not forget though, that when it comes to grapes DNA is not everything: remember that grapes as different as Pinot Gris, Pinot Blanc and Pinot Noir are indistinguishable when looking at their DNA!

Greetings / Fredrik L[/quote]

Fredrik - how can this be if they're not the same grape? Please educate me.

I'm still trying to figure out how in a recent thread it's *not* OK for "opportunistic" US winemakers to piggyback on Italian marketing by using "Brunello" on the labels of wine made from that clone of Sangiovese but it *is* OK for Italian winemakers to piggyback on Zinfandel's popularity in the US by labelling it that.

I share the bafflement on the DNA subject. Too bad Carole Meredith probably isn't around to straighten us out. I don't know what it can mean that Primitivo and Zinfandel (or the various Pinots) are genetically identical and yet different clones. Aren't different clones by definition genetically different? Are they in fact genetically identical or is it just that grape DNA testing is not yet capable of identifying the differences?

Thanks for the education Robin. I'm curious about your comments regarding artificial corks and aging. I've been reading a decent amount about closures, the problems with corks, the virtues (maybe) of screwtops, but I've not heard that artificial corks don't allow a wine to age properly. I can guess that the issue has to do with oxygen, but could you elaborate?

I

I share the bafflement on the DNA subject. Too bad Carole Meredith probably isn't around to straighten us out. I don't know what it can mean that Primitivo and Zinfandel (or the various Pinots) are genetically identical and yet different clones. Aren't different clones by definition genetically different? Are they in fact genetically identical or is it just that grape DNA testing is not yet capable of identifying the differences?

First of all, it is possible for two genetically identical organisms to show different characteristics. This is accomplished by proteins that control the expression of genomic DNA; this aspect of genetics is now referred to as "epigenetics." Fairly recently, an article in the prestigious journal Nature demonstrated that epigenetic differences account for much of the difference seen in identical twins.

Secondly, I spoke with Prof. Meredith about this subject when visiting her winery in late December. These various "clones" are in fact different mutants. This terminology is used to distinguish clonal variation from varietal variation that arises from sexual reproduction. So, Zinfandel and Primitivo aren't genetically identical, but the variation between their genomes is consistent with random mutagenesis from a common ancestor (which is though to be similar if not identical to Crljenik Kasteljanski).

Mark Lipton

[Robin Garr]

Thanks for the education Robin. I'm curious about your comments regarding artificial corks and aging. I've been reading a decent amount about closures, the problems with corks, the virtues (maybe) of screwtops, but I've not heard that artificial corks don't allow a wine to age properly. I can guess that the issue has to do with oxygen, but could you elaborate?

Bob, I'm not a chemist, nor do I play one on TV! Dr. Lipton may be able to help us out here, but to make a long story short, I think the wine geek community is in substantial agreement that, based on a considerable amount of anecdotal evidence, the synthetic/plastic corks are not proving out for long-term cellaring, and most producers who use them now are using them only for "drink-me-now" wines. I've had a LOT of five-year-old wines showing tired and short on fruit, particularly Rhone reds and other types that really should be just coming into their own, and I gather that I am far from alone on this. David Schildknecht mentioned to me at a tasting a couple of years ago when I asked about one of his then-employer's imports with a synthetic, and he said they were pulling away from using them on anything but whites intended for consumption within a year or two.

Mark
Never an easy distinction to establish as it's more about trade agreement than a clearly definable law drawn up on obvious boundaries.

IMO this is a bit like the example on the other thread - Sonoma Sangiovese (Brunello clone). The concensus was that whilst still seeking to utilise the name Brunello, gives prominance to the actual region/grape before acknowledging the other name. Acceptable perhaps (maybe not to the Brunello producers!), but even then potentially dubious.

Likewise this gives prominance to he Italian name of the grape and it's region, only then linking in to the US name for the grape. Again perhaps acceptable, but somewhat dubious.

What might be unacceptable? Calling an Italian cabernet blend 'Meritage' - a name developed exclusively in the US to denote a particular style of wine. Ditto calling a wine Brunello di Sonoma.

I guess I see both sides:
- plagiarism is seeking to piggy-back on someone else's hard work & endeavours, often with an inferior product in the hope that plenty of people wouldn't understand the difference.
- protectionism aims to corner a section of the market and use historic precedent (or other methods)to prevent competition, irrespective of the quality of the product itself.

As wine drinkers I reckon we should be seeking the middle ground on this as both extremes are undesirable. The middle ground tends to have a range of opinions still!

regards

Ian

What might be unacceptable? Calling an Italian cabernet blend 'Meritage' - a name developed exclusively in the US to denote a particular style of wine.

No problem with that.

It is a made up trademarked name that any winery that joins the Meritage Association can use on payment of a nominal amount per case made of accepted varieties.

Used to be that they wouldn't let non-US wineries join, but now it seems that they do accept international members, with members from six non-US countries, including France!

Peter
That's interesting - thanks for that.
regards
Ian

I share the bafflement on the DNA subject. Too bad Carole Meredith probably isn't around to straighten us out. I don't know what it can mean that Primitivo and Zinfandel (or the various Pinots) are genetically identical and yet different clones. Aren't different clones by definition genetically different? Are they in fact genetically identical or is it just that grape DNA testing is not yet capable of identifying the differences?

Actually she is. Well, at least her comments reside on my hard drive. I have posted this before. Hopefully it responds to your question.

The Difference between a “Variety” and a “Clone”
Dr. Carole Meredith on WineLoversPage BB

Zinfandel and Primitivo and Crljenak kastelanski are 3 names used for 1 variety. All three are the same variety, just like the synonyms Syrah/Shiraz or Tempranillo/Valdepenas. Although the variety has been in Croatia much longer than in Italy or the United States, Zinfandel is not “descended” from Crljenak in the genetic sense. Zin and Primitivo and Crljenak are all derived by vegetative multiplication (i.e., cuttings and buds) from a single original seedling.

Yes, there are clearly some differences between the vines called Zinfandel that we have been growing in California for 100+ years and those grown in Italy and called Primitivo. But those differences are clonal differences, not varietal differences. They are the same kinds of differences that can be observed between some clones of Syrah or between some clones of Chardonnay.

Here’s my boilerplate explanation of the distinction between clones and varieties:

DNA studies have clarified the distinction between a variety and clone. All vines of all clones of a variety are derived (by asexual propagation, i.e. cuttings and buds) from a single original vine. The single original vine arose as a seedling that was the result of a sexual union between two parent vines, almost always of two different varieties. All clonal variation, on the other hand, arises as a result of rare and random somatic mutations (i.e., not sexual) that occur in all vines. Sometimes such a mutation has a visible or otherwise detectable (e.g. aroma difference) effect and a vine carrying it will be preferentially used for propagation wood for new vineyards. But often it is just chance that one mutation survives to the next generation of vineyards and another doesn't. The mutations accumulate over time and eventually clones diverge from each other.

But clonal differences are very very tiny compared to the genetic differences between varieties. The standard DNA markers used to identify grape varieties will produce the same DNA profile for all clones in the variety. It took us years before we finally found any DNA markers at all that would separate any clones of Pinot or Chardonnay, and they only differentiated a few clones. The differences between varieties have their origin in sexual genetic processes (i.e., meiosis and recombination) whereas the differences between clones arise only from asexual processes.

This discussion becomes problematic in the case of Pinot noir, Pinot blanc, Pinot gris and Meunier, however, in that they are all, in fact, clones of a single variety (i.e., they all arose from a single original seedling and all have the same DNA profile) even though wine producers and consumers consider them to be separate varieties because they are so visibly different. The French language deals with this concept better in that all 4 are considered to be the same 'cepage'.
(end of boilerplate)

DNA profiling unambiguously distinguishes between individuals that have originated from separate sexual events.

In humans, this means that DNA profiling can distinguish individual people from each other if they have originated from separate sexual events, but it cannot differentiate identical (i.e., monozygotic) twins.

In grapevines, this means that DNA profiling can distinguish individual varieties from each other (like Chardonnay vs. Melon or Cabernet vs. Merlot) because they originated from separate sexual events, but it cannot differentiate clones within the same variety because they originated from a single sexual event.

Carole Meredith
University of California, Davis (sometimes)

Zin versus Primitivo debate! Cool! Had a Dillian (Foothills California) Zinfandel last year that illustrated why I don't drink a lot of Zin: thick, syrupy, sweet, etc. The PRIMITIVO was much more medium-bodied and very nicely brambly-spicy-and I loved it.

Mark and Gary have obviously given the necessary DNA information, no need to discuss that further other than to mention my Burgundian friend who when I scold him for using Pinot Beurot (Gris) in his wines in a illegal manner, always replies: "But it is the same grape!"

Greetings / Fredrik L

Bob, I'm not a chemist, nor do I play one on TV! Dr. Lipton may be able to help us out here, but to make a long story short, I think the wine geek community is in substantial agreement that, based on a considerable amount of anecdotal evidence, the synthetic/plastic corks are not proving out for long-term cellaring, and most producers who use them now are using them only for "drink-me-now" wines. I've had a LOT of five-year-old wines showing tired and short on fruit, particularly Rhone reds and other types that really should be just coming into their own, and I gather that I am far from alone on this. David Schildknecht mentioned to me at a tasting a couple of years ago when I asked about one of his then-employer's imports with a synthetic, and he said they were pulling away from using them on anything but whites intended for consumption within a year or two.

I believe you, but would love to know why. Those synthetic corks are so darn hard to get out (I always have to reach for the heavy duty 2 handle cork screw to remove them) it would seem they make a perfect seal. Isn't oxygen the enemy of wine, at least in the long term? Is there something about cork that allows a slight amount of breathing that helps the maturing process? Do they fail over time?

Bob, I'm not a chemist, nor do I play one on TV! Dr. Lipton may be able to help us out here, but to make a long story short, I think the wine geek community is in substantial agreement that, based on a considerable amount of anecdotal evidence, the synthetic/plastic corks are not proving out for long-term cellaring, and most producers who use them now are using them only for "drink-me-now" wines. I've had a LOT of five-year-old wines showing tired and short on fruit, particularly Rhone reds and other types that really should be just coming into their own, and I gather that I am far from alone on this. David Schildknecht mentioned to me at a tasting a couple of years ago when I asked about one of his then-employer's imports with a synthetic, and he said they were pulling away from using them on anything but whites intended for consumption within a year or two.

I believe you, but would love to know why. Those synthetic corks are so darn hard to get out (I always have to reach for the heavy duty 2 handle cork screw to remove them) it would seem they make a perfect seal. Isn't oxygen the enemy of wine, at least in the long term? Is there something about cork that allows a slight amount of breathing that helps the maturing process? Do they fail over time?

Really, the person to address this would be Stuart Y., but in his absence I'll mention that early on those synthetic corks were shown to chemically react with the sulfites in the wine, thereby removing most of the protection against oxidation and leading to premature aging. I've recently heard stories indicating that some of the fake corks might be far more permeable to gases than cork, which would also result in greater gas exchange and consequently oxidation (note that the seal is only one route for gas exchange -- if the closure is permeable it doesn't matter how tight the seal is). I await more authoritative responses, though.

Mark Lipton

Primitivo and Zin, you sure know how to get a discussion going. I worked at a winery were one year we bottled Zin and Primitivo. The next year all those grapes went into a bottle that said Zin on it.

Robin funny you mentioned the earthy descriptor for Primitivo. The first year we made wine from our Zinfandel vineyard the earthy taste that it had just blew me away. I had never tasted earthy in Zin before. We still get hints of earth in the wine from that vineyard but not like that first year. The Zin I make is not really high in alcohol either. I wonder if there is a connection?

Primitivo or Zinfandel?
It was only as recently as 2001 that modern grape sleuths, including Dr. Carole Meredith of the University of California at Davis, used DNA technology to confirm that Zinfandel and Primitivo are the identical grape, albeit different clones; and the same is true of the little-known Crljenik Kasteljanski of Croatia, which is now thought to be the original variety, exported to Italy as Primitivo and to the U.S. as Zinfandel.


Frankly, and probably more because of differences in wine-making styles than in fruit or <i>terroir[/i], I have rarely found Primitivo and Zinfandel all that similar. There's often a berry-like character in both, but differences typically fall acros the usual Old World-New World lines, with most Zins landing on the big fruit, high-alcohol side, while Primitivo tends to lower alcohol and hints of earth, plus a whack of oak if the producer wants to impress the critics.

Robin,
As implied in posts above, Carole did not identify Zin & Primitivo as different clones of the same grape. The technology can only identify
them as an identical variety, but cannot distinguish betwixt clones. That is done out in the vnyd.

As Steve mentions, George Hendry makes both a Primitivo and a Zin. The two vintages I've tasted side by side were distinctly different, but still had a lot of commonality. The folks I've talked to who grow Primitivo swear by it as greatly superior as a wine and as a variety to grow.

I've had a few (Italian) Primitivos that I thought could be confused w/ (Calif) Zins, but most of the Italian versions I've had haven't held a candle to any halfway decent Calif Zins. Often I think it's crude winemaking. Maybe it's even the..(careful...her comes the dreaded T-word)...terroir?

Interesting thread w/ lots of good comments.
Tom

Secondly, I spoke with Prof. Meredith about this subject when visiting her winery in late December. These various "clones" are in fact different mutants. This terminology is used to distinguish clonal variation from varietal variation that arises from sexual reproduction. So, Zinfandel and Primitivo aren't genetically identical, but the variation between their genomes is consistent with random mutagenesis from a common ancestor (which is though to be similar if not identical to Crljenik Kasteljanski).

Mark, thanks for the lesson. Some of this is vaguely familiar from an earlier thread on this topic, it's slowly sinking in Isn't what you've said here consistent with my shot in the dark: that clones are, in fact, genetically different, it's just that the available DNA profiling technology can't distinguish between them? Can you offer an explanation a lay person can understand on why the technology can identify genetic differences between what Dr. Meredith called in Gary's quote "separate sexual events" but not genetic differences resulting from mutation? It seems like if one had a complete genetic map of two different clones, the difference would have to be there. Is it just that nobody's going to invest the time in money in doing a complete map of the Zinfandel genome and practical DNA profiling can't find the relatively small differences caused by mutation?

Lots of questions, I know. One last one: if DNA profiling can't find the genetic differences between clones, can it be relied upon to find the differences between the results of two different sexual events? In my readily apparent ignorance about genetics, I have no feel for the statistics involved.

Mark W.

Mark, thanks for the lesson. Some of this is vaguely familiar from an earlier thread on this topic, it's slowly sinking in Isn't what you've said here consistent with my shot in the dark: that clones are, in fact, genetically different, it's just that the available DNA profiling technology can't distinguish between them?

Yup.

Can you offer an explanation a lay person can understand on why the technology can identify genetic differences between what Dr. Meredith called in Gary's quote "separate sexual events" but not genetic differences resulting from mutation? It seems like if one had a complete genetic map of two different clones, the difference would have to be there. Is it just that nobody's going to invest the time in money in doing a complete map of the Zinfandel genome and practical DNA profiling can't find the relatively small differences caused by mutation?

Well, there is a completely sequenced grape genome for Pinot Noir. It was published last year IIRC in Science, which gives you an idea of how tough a task it is. Yes, it would be too expensive/labor intensive to sequence their DNA to single nucleotide resolution. Instead, what they did (and what is done in forensics labs for DNA profiling) is that the DNA is digested with a "restriction endonuclease," an enzyme that chops DNA at sites that have a certain base sequence (e.g., ATCCTA), and the fragments produced are separated by size. The pattern of fragments (the number and their sizes) is compared to another sample to establish identity. This is referred to as RFLP (Restriction Fragment Length Polymorphism).

So, clonal variation, which might involve only changing a few dozen nucleotides in a genome of several million nucleotides, might show no or only a subtle difference in the pattern produced.

Lots of questions, I know. One last one: if DNA profiling can't find the genetic differences between clones, can it be relied upon to find the differences between the results of two different sexual events? In my readily apparent ignorance about genetics, I have no feel for the statistics involved.

Sexual reproduction involves wholesale swapping of genetic material, with accompanying huge changes to the DNA. In this case, RFLP analysis should show big differences, though closely related varieties should show fewer differences than unrelated ones.

Mark Lipton

Sexual reproduction ........
Mark Lipton

I love it when we got this thread drift here on WLDG!!!

Thanks for clarifying things, Mark. So using DNA techniques for differianting clones in not impossible. It just requires the sequencing of
the entire genome and that is very expensive is what I understand you are saying??
Tom

Mark, thanks for the lesson. Some of this is vaguely familiar from an earlier thread on this topic, it's slowly sinking in Isn't what you've said here consistent with my shot in the dark: that clones are, in fact, genetically different, it's just that the available DNA profiling technology can't distinguish between them?

Yup.

Can you offer an explanation a lay person can understand on why the technology can identify genetic differences between what Dr. Meredith called in Gary's quote "separate sexual events" but not genetic differences resulting from mutation? It seems like if one had a complete genetic map of two different clones, the difference would have to be there. Is it just that nobody's going to invest the time in money in doing a complete map of the Zinfandel genome and practical DNA profiling can't find the relatively small differences caused by mutation?

Well, there is a completely sequenced grape genome for Pinot Noir. It was published last year IIRC in Science, which gives you an idea of how tough a task it is. Yes, it would be too expensive/labor intensive to sequence their DNA to single nucleotide resolution. Instead, what they did (and what is done in forensics labs for DNA profiling) is that the DNA is digested with a "restriction endonuclease," an enzyme that chops DNA at sites that have a certain base sequence (e.g., ATCCTA), and the fragments produced are separated by size. The pattern of fragments (the number and their sizes) is compared to another sample to establish identity. This is referred to as RFLP (Restriction Fragment Length Polymorphism).

So, clonal variation, which might involve only changing a few dozen nucleotides in a genome of several million nucleotides, might show no or only a subtle difference in the pattern produced.

Lots of questions, I know. One last one: if DNA profiling can't find the genetic differences between clones, can it be relied upon to find the differences between the results of two different sexual events? In my readily apparent ignorance about genetics, I have no feel for the statistics involved.

Sexual reproduction involves wholesale swapping of genetic material, with accompanying huge changes to the DNA. In this case, RFLP analysis should show big differences, though closely related varieties should show fewer differences than unrelated ones.

Mark Lipton

Thanks for your usually thorough answer, Mark. But you can stop there