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In recent weeks, Nicholas Wade’s book A Troublesome Inheritance has been soundly criticized on the basis of his misunderstanding (or misrepresentation) of the statistical methods used to study human genetic variation (see Jeremy Yoder’s critique here, Chris Smith’s here, Joseph Graves’ here, and mine here ), his misunderstanding of evolution (see Michael Eisen’s critique here, and Eric Michael Johnson’s here ), and his misunderstanding of human biological variation (see Greg Laden’s critique here,  Agustin Fuentes’ critique here, and Jon Marks’ here ). These criticisms–all from biologists and biological anthropologists– can be boiled down into a single statement: Mr. Wade’s book is scientifically unsound.

His responses thus far (to those of us who published in the Huffington Post) have failed to engage any of the substantive issues that have been raised. Instead, he dismissed our standing for discussing this issue, calling me a “postdoctoral student” (A science journalist should be aware that postdocs aren’t students), and dismissing Dr. Fuentes’ and Dr. Marks’ research background and credentials (as if biological anthropologists were not scientists). I have not seen any response yet to the numerous other critiques from biologists that have appeared elsewhere (many listed in the previous paragraph), which raise many of the same concerns.

Mr. Wade may feel that he can ignore the substantive critiques of his book by scientists. But can he do the same for fellow science journalists? David Dobbs’ review of Mr. Wade’s book appeared in the New York Times Book Review this past Sunday (the online version can be read here). It is not favorable.  Mr. Dobbs calls the book “deeply flawed, deceptive, and dangerous.”

In discussing the study (critiqued by most of us above) that Mr. Wade claims supports the genetic basis for three (or is it five?) “continental races”, Mr. Dobbs notes that the paper itself

“directly contradicts Wade’s argument. Yet he baldly claims the study as support.  And he does this sort of thing repeatedly: He constantly gathers up long shots, speculations and spurious claims, then declares they add up to substantiate his case. The result is a deeply flawed, deceptive and dangerous book.”

Mr. Dobbs elaborates on this in the companion piece on his blog:

“Wade demonstrates how a lucid, well-written, selective presentation of evidence — eloquent, elegant cherry-picking — can convince smart people of pernicious ideas that seem scientific, but which science does not support. Much of the sleight of hand in this book will not be evident to people who don’t know the field. In some cases one has to read a specific paper cited by Wade to recognize that he thoroughly misrepresents its findings.”

I encourage you to go read both of Mr. Dobbs’ critiques. It will be interesting to see how Mr. Wade responds.

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Update: Here are a few other critiques worth mentioning:

A Troublesome Ghost by Dr. John Edward Terrell

In addition to the post I cited above, Dr. Chris Smith also takes on Wade’s mischaracterization of
the genetic basis for violent behavior in different populations.

He also discusses in detail Wade’s repeated assertion that human evolution has been “recent, copious and regional”.

And if you’d like to listen to an interesting discussion on race, genetics, ancestry testing, and human biology, here’s an appearance by Agustin Fuentes on the Center for Environmental Health podcast.

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Nicholas Wade has a problem. Although his new book, “A Troublesome Inheritance: Genes, Race and Human History”, appears to be selling well, he’s not encountering the praise that he expected from biologists for “courageously” freeing them from the “intimidating social scientists” on the subject of race).

Plus ça change, plus c'est la même chose

Plus ça change, plus c’est la même chose

 

 

What is he arguing? I go over this briefly in my recent piece on the Huffington Post, and in much greater detail here on this blog, but essentially Wade is using patterns of human variation in populations as a justification for claiming that race is a valid, biological taxonomic category. He goes on to speculate (and that’s really the only word for it, since his claims are unsupported by the preponderance of scientific evidence) that these racial differences determine behavioral differences and thereby explain why some civilizations have historically been more successful economically and politically than others. (You can guess which races he’s talking about; his speculation happens to coincide neatly with traditional stereotypes.)

Wade claims that all critics of this viewpoint are motivated by political concerns and ignore data showing that races are genetically distinct enough to be meaningful taxonomic categories of humans. His book relies particularly upon one genomics study to support this point. In his words (emphasis mine):

 

Raff and Marks take issue with one of these surveys, Rosenberg et al. 2002, which used a computer program to analyze the clusters of genetic variation. The program doesn’t know how many clusters there should be; it just groups its data into whatever target number of clusters it is given. When the assigned number of clusters is either greater or less than five, the results made no genetic or geographical sense. But when asked for five clusters, the program showed that everyone was assigned to their continent of origin. Raff and Marks seem to think that the preference for this result was wholly arbitrary and that any other number of clusters could have been favored just as logically. But the grouping of human genetic variation into five continent-based clusters is the most reasonable and is consistent with previous findings. As the senior author told me at the time, the Rosenberg study essentially confirmed the popular notion of race.

 

It’s not a question of logic, but rather what the data show. Rosenberg et al. (2002)’s paper did not analyze or identify just 5 clusters, but rather it considered 1-20 clusters. What Wade is omitting from his paragraph above (and also from his book) is that Rosenberg and colleagues never presented any statistical justification for the choice of 5 clusters over any other number.

Here are the specifics of my criticism, which I posted in response to a commenter on my blog. (If you’re not interested in the statistical refutation of Wade’s argument, feel free to skip this paragraph. I hope Wade takes the time to read it, though). Continue Reading…

“…for he has no right to give names to objects which he cannot define.” –Charles Darwin

Do “races” exist as meaningful biological categories? Physical anthropologists and human biologists have been studying race (i.e., blacks vs. whites, or Europeans vs. Asians) for centuries. For most of that time, they subscribed to the perspective that race was a taxonomic category, and they sought to identify the biological characteristics (such as cranial shape or skin color) that characterized and defined these different groups. This perspective assumed that each individual was a member of a single racial category, that the differences between racial categories were biological, and that these categories were predictive of other traits (such as ancestry, temperament, intelligence, or health).

But it gradually became clear that this understanding was not scientifically sound. Groupings of people by skin color did not produce the same result as groupings of people by skull shape, nor of blood type. Furthermore, as scientists began to study human variation with the tools of genetics (in the process creating my fields, anthropological genetics and human population genetics), it became apparent that human genetic variation does not divide humans into a few discrete groups. There are virtually no sharp boundaries, either with physical features or with patterns of genetic diversity, that show where one population “ends” and the next “begins”. Continue Reading…

This is the second post in a series discussing the recent publication of a 12,500 year old genome from Montana. You can find the first post here.

In the weeks following the publication of the complete genome from a Clovis child, there’s been a lot of press coverage of this study and its possible implications. I want to discuss a bit of the media coverage on this subject, since it raises issues that I think science journalists need to consider more carefully.

First of all, to recap the major findings of the original study (discussed in more detail at the link above):
1. Anzick-1, the 12,500 year old Clovis child whose genome Rasmussen and colleagues sequenced, is very closely related to living and ancient Native Americans.
2. Anzick-1 is more closely related to Siberians than other Eurasian groups.
3. Anzick-1 is more closely related to Central and South American Native American groups than to some North American groups.
4. The results from Anzick-1’s genome fit with the scientific consensus about the peopling of the Americas. This consensus encompasses the results of decades of archaeological, genetic, and paleoclimate research.

Unfortunately, several press reports chose to find controversy in a decidedly non-controversial story by giving undue weight to problematic “alternative” explanations of Native American origins, including the Solutrean hypothesis, and other “European contributions” to Native American ancestry.

140214_NEWSCI_NativeAmeGenome.jpg.CROP.promovar-medium2

Clovis tools from the Anzick site. From Rasmussen et al. 2014.

Continue Reading…

Last Wednesday, Dr. Morton Rasmussen of the Natural History Museum of Denmark and his colleagues announced that they had completely sequenced the genome of an infant boy, buried ~12,600 years ago in Montana. A few weeks earlier, I’d been approached by an editor at Nature, who asked me if I and my mentor Deborah Bolnick would be interested in writing a companion paper that would analyze and contextualize their results. We agreed, and the paper was published in last week’s issue, alongside Rasmussen et al.’s work. Because it’s (unfortunately) behind a paywall, I’d like to summarize what we said in that paper for non-scientists. There are a lot of things to talk about with regard to this study, including a consideration of ethical issues and the media’s response, so I’m likely going to do several posts on it. This first post is mainly a discussion of how we interpret the results.

For a TL;DR version of this post, here’s a link to a short interview I did on the subject last week with the BBC World Service.
Continue Reading…

Nature publication

Jennifer Raff —  February 12, 2014 — Leave a comment

I haven’t been writing as much here recently, because I’ve been working on a “News and Views” article for Nature….and now I can finally talk about it! Here’s a link to my article: http://www.nature.com/nature/journal/v506/n7487/full/506162a.html, and to the paper that it’s discussing: http://www.nature.com/nature/journal/v506/n7487/full/nature13025.html. In the next few days I’ll post something here to discuss the main points of the article (for those of you who can’t access it), and also my reaction to the media coverage that the study is getting.

“You’re going against 40,000 years of evolution”

“This innate toughness that men have is crucial to our survival.”

These points, and many others along the same lines, were made by Mr. Gavin McInnes, author of “How To Be a Man” in a recent discussion of masculinity on the Huffington Post. His argument is based on a suite of assumptions common in our culture. It often forms the basis of misogynist arguments against feminism. Basically:

1. Evolution has made men naturally more “aggressive and tough”, and women naturally more “compassionate and domestic”.

2. Therefore in the modern world, as in past societies, men are the natural breadwinners, and women the natural caretakers of the home/children.

3. Going against these gender norms, as feminism has done in the last few decades, is going against nature, and disrespectful of the importance of childcare!

According to Mr. McInnes, women who work outside the home are “forced to pretend to be men. They’re feigning this toughness. They’re miserable.” You’ll hear a lot of people agreeing with this line of reasoning. But is it scientifically based? Continue Reading…

Cutting edge science

Jennifer Raff —  July 9, 2013 — 1 Comment

I’m attending my first Society for Molecular Biology and Evolution conference this week, and learning about some terrific research that my colleagues are doing. I just thought I’d share a few of the really neat things I’ve learned today.
Continue Reading…

Today the United States Supreme Court issued a unanimous ruling on a case very important to genetics research and medicine.*

In ASSOCIATION FOR MOLECULAR PATHOLOGY V. MYRIAD GENETICS, INC., the Supreme Court addressed the question of whether genes could be patented. The defendant, Myriad Genetics, had identified and patented two very important genes implicated in breast and ovarian cancer: BRCA1 and BRCA2. Their patents meant that they had exclusive rights to sell genetic tests to identify the cancer-causing mutations in these genes, and controlled any research on them.

The Supreme Court ruled against Myriad Genetics. In their opinion, written by Justice Thomas, they stated that:

“a naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated, but that cDNA is patent eligible because it is not naturally occurring.”

cDNA has an identical sequence to the original gene, but has been synthesized from a messenger RNA copy of the gene with the non-coding portions (introns) removed. Here is a little tutorial that explains more about cDNA. (Perhaps Justice Scalia should watch it.**) Having a direct ‘read-out’ of the coding bits of a gene is necessary for many molecular biology applications, and this ruling is important to biotech companies (who have been patenting cDNA all this time).

This ruling is excellent news. It recognizes that the human genome isn’t ‘property’, which would have had a seriously detrimental effect on future genetics research and personalized medicine. It also means that all companies offering screens for cancer-causing variants can finally include BRCA1 and BRCA2 along with other genes tested. That will hopefully improve access to genetic information for many women with concerns about familial histories of breast and ovarian cancer, and allow them to make informed decisions about their health in advance of cancer appearing.

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*There’s a lot of discussion going on among geneticists about how badly the Supreme Court bungled the science. And it’s true that they made a lot of errors. However, I’d point out that most of us geneticists in turn probably don’t understand a lot about patent law.

**Justice Scalia issued a very odd opinion in which he agreed with the other justices about the outcome but as to the details of molecular biology:

” I am unable to affirm those details on my own knowledge or even my own belief.”

Belief? It’s perfectly reasonable to admit you don’t understand the science, but it seems strange to state that you may not believe it. This isn’t exactly controversial stuff. I’m very curious why he chose that word.

Further reading:
SCOTUS blog on the ruling: http://www.scotusblog.com/2013/06/opinion-recap-no-patent-on-natural-gene-work/

A nice discussion of the issues: http://www.pbs.org/wgbh/nova/next/body/gene-patents-and-personalized-medicine/

Do you want access to all government-funded genetic research results? You can download whatever you want (for free) here: http://www.ncbi.nlm.nih.gov/genbank/