That is the question, and tentatively answered in the affirmative according to a new paper in The American Journal of Physical Anthropology. A new subclade of mtDNA haplogroup C1 found in icelanders: Evidence of pre-columbian contact?:

Although most mtDNA lineages observed in contemporary Icelanders can be traced to neighboring populations in the British Isles and Scandinavia, one may have a more distant origin. This lineage belongs to haplogroup C1, one of a handful that was involved in the settlement of the Americas around 14,000 years ago. Contrary to an initial assumption that this lineage was a recent arrival, preliminary genealogical analyses revealed that the C1 lineage was present in the Icelandic mtDNA pool at least 300 years ago. This raised the intriguing possibility that the Icelandic C1 lineage could be traced to Viking voyages to the Americas that commenced in the 10th century. In an attempt to shed further light on the entry date of the C1 lineage into the Icelandic mtDNA pool and its geographical origin, we used the deCODE Genetics genealogical database to identify additional matrilineal ancestors that carry the C1 lineage and then sequenced the complete mtDNA genome of 11 contemporary C1 carriers from four different matrilines. Our results indicate a latest possible arrival date in Iceland of just prior to 1700 and a likely arrival date centuries earlier. Most surprisingly, we demonstrate that the Icelandic C1 lineage does not belong to any of the four known Native American (C1b, C1c, and C1d) or Asian (C1a) subclades of haplogroup C1. Rather, it is presently the only known member of a new subclade, C1e. While a Native American origin seems most likely for C1e, an Asian or European origin cannot be ruled out.

The core of the article treads the confusing gray zone between rock-hard precise science and the more vague and intuitive truths of history. One the rock-hard part, there is a huge literature on maternal genetic lineages, the mtDNA. Because this genetic material is copious it was some of the first to be analyzed using molecular clock models. A molecular clock is a feasible with mtDNA because it is haploid; it is only inherited through females and so is not subject to recombination which might break apart associations of distinctive genetic markers. Instead of being a reticulated mesh the genealogy of mtDNA is a clean and inverted elegant tree leading back to a common ancestress. You are finding the line of your mother’s mother’s mother’s mother’s….

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David Kirkpatrick, author of The Facebook Effect, has a breathless take on the rise of Facebook and its impending assault on Google in The Daily Beast. There’s a lot of hyperbole and Facebook-cheering throughout the piece, but this bold but unsupported assertion caught my attention:

Email is, as we all know, a horribly broken system. It is what almost all of us lean on the most heavily to get our work done. Yet we all know it is inefficient and unwieldy. Now Facebook’s innovations aim to use its so-called “social graph,” the set of relationships you have with another user, to remake daily electronic communication.

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The number 1 gets a lot more press than -1, and the concept of heterozygosity gets more attention than homozygosity. Concretely the difference between the latter two is rather straightforward. In diploid organisms the genes come in duplicates. If the alleles are the same, then they’re homozygous. If they’re different, then they’re heterozygous. Sex chromosomes can be an exception to this because in the heterogametic sex you generally have only one copy of gene as one of the chromosomes is sharply truncated. This is why in human males are subject to X-linked recessive traits at such a great frequency in comparison to females; recessive expression is irrelevant when you don’t have a compensatory X chromosome to mask the malfunction of one allele.

Of course recessive traits are not simply a function of sex-linked traits. Consider microcephaly, an autosomal recessive disease. To manifest the trait you need two malfunctioning copies of the gene, one from each parent. In other words, you exhibit a homozygous genotype with two mutant copies. I suspect that this particularly common context of homozygosity, recessive autosomal diseases, is one reason why it is less commonly discussed outside of specialist circles: there are whole cluster of medical and social factors which lead to homozygosity which are already the focus of attention. The genetic architecture of the trait is of less note than the etiology of the disease and the possible reasons in the family’s background which might have increased the risk probability, especially inbreeding. In contrast heterozygosity is generally not so disastrous. Even if functionality is not 100%, it is close enough for “government work.” The deleterious consequences of a malfunctioning allele are masked by the “wild type” good copy. The exceptions are in areas such as breeding for hybrid vigor, when heterozygote advantage may be coming to the fore. The details of complementation of two alleles matter a great deal to the bottom line, and the concept of hybrid vigor has percolated out to the general public, with the more informed being cognizant of heterozygosity.

But homozygosity is of interest beyond the unfortunate instances when it is connected to a recessive disease. Like heterozygosity, homozygosity exists in spades across our genome. My 23andMe sample comes up as 67.6% homozygous on my SNPs (which are biased toward ~500,000 base pairs which tend to have population wide variation), while Dr. Daniel MacArthur’s results show him to be 68.1% homozygous across his SNPs. This is not atypical for outbred individuals. In contrast someone whose parents were first cousins can come up as ~72% homozygous. This is important: zygosity is not telling you simply about the state of two alleles, in this case base pairs, it may also be telling you about the descent of two alleles. Obviously this is not always clear on the base pair level; mutations happen frequently enough that even if you carry two minor alleles it is not necessarily evidence that they’re identical by descent (IBD), or autozygous (just a term which denotes ancestry of the alleles from the same original copy). What you need to look for are genome-wide patterns of homozygosity, in particular “runs of homozygosity” (ROH). These are long sequences biased toward homozygous genotypes.

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TechCrunch is reporting on Facebook’s new “modern messaging system”. The first few comments immediately telegraphed my first impression: is this Facebook’s Google Wave? Interesting then to see if Facebook can make this work. If it can’t, then score one for the proposition that people don’t want a seamless integration of various tools which emerged in the 1990s and have distinctive roles today in the information ecology (IM, email, message boards, etc.). If Facebook succeeds perhaps it goes to show the importance of timing, execution and marketing. On the other hand, Mashable makes MMS sound just like a souped-up version of SMS texting, and so far less ambitious in scope than Wave ever was. Email is more formal, which is why it can be very useful in some situations. Facebook is more convenient for getting in touch with your college roommate.

Ruchira Paul has her own reaction to Zadie Smith’s pretentious review of The Social Network. One of the aspects of Smith’s review which Ruchira focuses upon is her concern about the extinction of the “private person.” I have mooted this issue before, but I think it might be worthwhile to resurrect an old hobby-horse of mine: is privacy as we understand it in the “modern age” simply a function of the transient gap between information technology and mass society? In other words, for most of human history we lived in small bands or in modest villages. These were worlds where everyone was in everyone else’s business. There was very little privacy because the information technology was well suited to the scale of such societies. That “technology” being our own innate psychology and verbal capacities. With the rise of stratified cultures elites could withdraw into their own castles, manses and courtyards, veiled away from the unwashed masses. A shift toward urbanization, and greater anonymity made possible by the rise of the mega-city within the last few centuries, has allowed the common citizen to also become more of a stranger to their neighbors. It is far easier to shed “baggage” by simply moving to a place where everyone doesn’t know your name.

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I am not doing daily link round ups right now because I’m not reading the web as much, but I certainly have enough material to put up one link round-up/pointer per week.

David Burbridge of GNXP has completed five posts on the Price equation. One more to go (focusing on group selection). Highly recommended.

Vitamin D Deficit Doubles Risk of Stroke in Whites, but Not in Blacks, Study Finds. There has been other stuff about different healthy basal levels of micronutrients by population. This is an important one to keep an eye on, and should make us reflect on the importance of personalized medicine. A friend of mine who is a doctor observed that one reason that more well educated and higher socioeconomic status patients get better diagnoses and treatment is because they do so much leg-work and are so assertive as advocates for their own health.

Questionable Science Behind Academic Rankings. It’s long been known that academic rankings (like lists of all sorts) are 1) voodoo in terms of adding any real value beyond what you know, 2) crack in terms of profitability. US News & World Report wouldn’t even exist at this point if it wasn’t for their yearly rankings, and if the weekly folds I’m sure that their rankings could be spun-off as a profitable annual publication.

The Way the Future Blogs. Frederik Pohl’s memories. One of the things I really enjoyed about The Price of Altruism is that it gave me a wider lens on George Price the man, who I knew primarily through the recollections of W. D. Hamilton. Pohl does the same for the luminaries of the “Golden Age of Science Fiction.” I especially enjoy the stuff on Isaac Asimov.

Thoughtful Animal. A blog worth reading.

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One of the great things about Google Data Explorer is that it allows us to explore the quantitative magnitudes of qualitative differences which we have a general sense of intuitively. I’ve focused on the international data so far, but I thought I’d drill-down to the level of American states and metropolitan areas.

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Blogs worth checking out: Reaction Norm, A Replicated Typo, and Dodecad. Heather Mac Donald has some expectations for the Tea Party.

Take a look at the Wikio Science Top 20. Same old, same old. I’m always sniffing around for new science blogs, and am struck by how many of the top bloggers I’ve met personally. Eight of the top 20 on Wikio for example. Are there many unknown gems out there?

Josh Green reminisces about the rise of Talking Points Memo. Some people “have it”, some do not. Joshua Micah Marshall “has it.” He’s always had it. I started an abortive blog in the fall of 2001, but gave up after a week. Then I started blogging in April of 2002, and never looked back. For most of the 2000s I was a code monkey who blogged as a hobby on the side. I never managed to give it up, and it’s led me to some really awesome places.

Cultures differ. Check out the definition for ‘Islamophobia’. Now read this article, Palestinian held for Facebook criticism of Islam:

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Been a while since I did some bonus kat photos, so here it goes….

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1. First, a post from the past: Extremism in defense of precision is no vice.

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