eugenics in the news

from the u.k.’s telegraph (links added by me):

“Euroscience Open Forum 2012: DNA gene testing ‘will screen out lovers'”
13 Jul 2012

“Couples will soon be able to choose their life partner solely based on the compatibility of their genes instead of through love, a scientific conference has heard.

“Due to the falling cost of DNA testing Britain is on the cusp of a new era of eugenics, according to a leading British scientist.

“Prof Armand Leroi, of Imperial College London, said that within five to ten years it will be common for young people to pay to access their entire genetic code.

“He told the Euroscience Open Forum 2012, in Dublin, that a desire to have a healthy baby will lead more to request access to the view the genes of any prospective partner.

“Armed with this information, the couple could then use IVF to screen babies with incurable diseases.

“While it was unlikely people will have the ‘luxury’ of using the technology to design babies, by their intellect or eye colour, they would instead focus on stopping genetic diseases.

“Addressing a session titled ‘I human: are new scientific discoveries challenging our identity as a species’, he said the cost of genetic sequencing was falling so quickly that ‘it is going to become very, very accessible, very, very soon’….

“He said eugenics were already available, with tens of thousands of unborn babies with Down’s syndrome and other illnesses being aborted every year.

“He told the conference on Thursday: ‘These processes are very well established in most European countries.

“‘Many of the ethical problems that people raise when they speak of neoeugenics are nought once you offer gene selection or mate selection as a eugenic tool.'”

meanwhile, in tonga:

“Tonga’s Crown Prince Tupouto’a Ulukalala marries cousin”
12 July 2012

“The heir to the throne of Tonga in the South Pacific has married his second cousin in the capital Nuku’alofa.

“Crown Prince Tupouto’a Ulukalala and his bride, Sinaitakala Fakafanua, both in their 20s, waved to cheering crowds as they left church after the wedding…..

“Marriage between cousins is seen as a way of keeping the royal bloodline strong in Tonga….”

felicitations to the happy couple! (^_^) (seriously!)

previously: ivy league selective breeding

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evolution likes it hot

i posted about this before, but the topic came up in conversation recently, so i thought i’d post about it again:

“Evolution faster when it’s warmer”
24 June 2009

“Climate could have a direct effect on the speed of ‘molecular evolution’ in mammals, according to a study.

“Researchers have found that, among pairs of mammals of the same species, the DNA of those living in warmer climates changes at a faster rate.

“These mutations – where one letter of the DNA code is substituted for another – are a first step in evolution.

“The study, reported in Proceedings of the Royal Society B, could help explain why the tropics are so species-rich….

“The idea that microevolution happens faster in warmer environments is not new. But this is the first time the effect has been shown in mammals, which regulate their own body temperature.

“‘The result was unexpected,’ said Len Gillman from Auckland University of Technology, who led the study.

“‘We have previously found a similar result for plant species and other groups have seen it in marine animals. But since these are “ectotherms” – their body temperature is controlled directly by the environment – everyone assumed that the effect was caused by climate altering their metabolic rate….’

“‘We suspected the same effect might be happening in mammals, because seasonal changes affect the animals’ activity,’ Dr Gillman told BBC News.

“He and his team compared the DNA of 130 pairs of mammals, looking at genetically similar ‘sister species’ – where each of the pair lived at a different latitude or elevation.

“They tracked changes in one gene that codes for a protein known as cytochrome b, comparing the same gene in each of the pair of mammals to a “reference” gene in a common ancestor.

“By looking for mutations in the DNA code for this gene – each point where one letter in the code was substituted for another – the researchers were able to see which of the two mammals had ‘microevolved’ faster.

“Animals living in environments where the climate was warmer, had about 1.5 times more of these substitutions than the animals living in cooler environments.

“Dr Gillman explained that, at higher latitudes where environments are colder and less productive, animals often conserve their energy – hibernating or resting to reduce their metabolic activity.

“‘In warmer climates annual metabolic activity is likely to be greater, so this will lead to more total cell divisions per year in the germline.’

“These results support the idea that high tropical biodiversity is caused by faster rates of evolution in warmer climates.”

here’s the original research article: Latitude, elevation and the tempo of molecular evolution in mammals

one of the first things that popped into my mind — right after cool! — when hearing about this a few years ago was: so what could this mean for the out-of-africa (ooa) theory? one of the foundational pillars of ooa is that, because genetic variation is greatest in africans, they must be some of the oldest populations on earth ’cause they’ve acquired so many, many mutations — therefore, everyone else prolly came ooa:

“A 10-year study published in 2009 analyzed the patterns of variation at 1,327 DNA markers of 121 African populations, 4 African American populations, and 60 non-African populations. The research showed that there is more human genetic diversity in Africa than anywhere else on Earth….

“Human genetic diversity decreases in native populations with migratory distance from Africa and this is thought to be the result of bottlenecks during human migration, which are events that temporarily reduce population size. It has been shown that variations in skull measurements decrease with distance from Africa at the same rate as the decrease in genetic diversity. These data support the Out of Africa theory over the multiregional origin of modern humans hypothesis.”

but if genetic variation might be increased just by living in a hot climate … well … then what?

more recently, davidski over at eurogenes posted about this paper the other day: An Abundance of Rare Functional Variants in 202 Drug Target Genes Sequenced in 14,002 People. turns out african americans have a lot more rare genetic variants than europeans — and northern europeans have the least of all:

could the differences be related to the fact that these people’s ancestors came from different latitudes/climates and, so, their mutation rates were different? dunno. maybe.

previously: here’s my question

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more on consanguinity in england (and scotland)

below is a chart summarizing the findings from various consanguinity studies for england (and a couple for scotland). i’ve adapted catherine linley day’s chart which appears in her thesis [opens pdf] on pg. 245 (basically, i’ve added her findings, fleshed out darwin’s findings, and added a couple of others — i also divided the findings between north and south). most of these studies have drawbacks and lynley day goes through them all in detail on pages 245-250. click on image for LARGER view:

as you can see, and as i mentioned yesterday, the overall pattern seems to be that people in southern great britain have largely avoided cousin marriage since the 1500s (possibly as far back as the 1300s), while the people further north, not so much. if anything, cousin marriage increased in the succeeding centuries, particularly in the nineteenth (a general pattern for much of europe).

the sorts of cousin marriage rates we see for the english from the medieval period to the modern — ranging from 0.00 to 5.30 — are just not even in the same ballpark cricket pitch as other parts of the world like the arab peninsula or even southern europe. and they haven’t been. for centuries. the english, especially members of the southern subspecies, have apparently avoided cousin marriage like the plague.

there are gaps, i know. big gaps. more numbers would be nice, of course. further research is required. (~_^)

let me go through the list.

the first entry for fourteenth century ely. i posted about that here. fifty percent (50%) of all marriages in ely, cambridgeshire, in the 1300s were to people living outside of ely. hard to know if this means people were avoiding cousin marriage or not — people from ely could’ve been marrying their cousins living in other villages — but it’s likely, i think, that this means they were avoiding marrying close family members. at this point in time, the roman catholic church had banned cousin marriage up to and including third cousins, and as lynley day points out with regard to the second entry on the list (1500s england), for whatever reasons, medieval english people seemed to take these restrictions seriously [pg. 246]:

“Marriage dispensations from the reign of Henry VIII were used to estimate consanguinity (Smith et al. 1993). The results produced from these documents were surprisingly low (Table 6-4), with a total absence of 1st cousin marriages and a very low level of 2nd cousin marriages, even compared to modern studies. One possible explanation, as noted by Smith and his colleagues, is that the marriage dispensations may not reflect actual practice, although anecdotal evidence suggests that there was a real aversion to close consanguineous marriage in the mediaeval period (Smith et al. 1993). Another explanation proffered is that marriage dispensations were almost exclusively the preserve of the rich, and that the poor and labourers did not avail themselves of the system (Smith et al. 1993).”

the third item on the list is lynley day’s study which i posted about yesterday. the next is bramwell’s study for shropshire. bramwell used george darwin’s techniques to calculate cousin marriage rates in that county by looking at surnames. his results are not far off lynley day’s and so, i’d guess, are probably fairly accurate. the same can be said for darwin’s results (which i posted about here).

pearson’s hospital study involved checking for consanguinity between the parents of sick children. while consanguineous couples might have more sickly children on average compared to the rest of the population, pearson’s finding of 1.3% first cousin marriages for londoners of the time also seems to fit well with the other findings. he attempted to double-check his results by surveying the readers of the british medical journal (bmj), but he may have gotten a skewed response (only persons married to cousins responding) and/or many of the readers at the time may have been from the upper classes. one or both of those may account for the high (for england) 4.69% first-cousin marriage rate that he found.

the next study, bell’s study of hospital patients across england, had the same methodology as pearson’s, but found a slightly lower consanguinity rate. but the late nineteenth century/early twentieth century (when the study was conducted) is just the point when consanguinity rates started to drop across europe after peaking between 1875-1915, so that may account for the lower rates.

smith’s study of the records of the society of genealogy members probably has a slight bias towards middle-/upper-class folks who, as g. darwin showed, tend to have slightly higher consanguinity rates in england (and elsewhere, too, i think). finally, the study of consanguinity rates in twentieth century reading by coleman can be found here.

previously: consanguinity in england – north vs. south and but what about the english? and cousin marriage rates amongst nineteenth century english and english jews and exogamous marriage in medieval england and invention of the modern world

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consanguinity in england – north vs. south

in “Marriage Patterns in Two Wiltshire Parishes 1754-1914: Geographical Mobility, Consanguinity and Illegitimacy” [opens pdf], catherine linley day found that the average cousin marriage rates for stourton and kilmington parishes between the years of 1800 and 1914 were (pg. 243 – click on chart for LARGER view):

those are really low rates. the total average consangunity (first- AND second-cousin) rate is just 3.9%. going out all the way to include sixth cousins, the cousin marriage rate is still only 9.2%.

wiltshire is in sw england and is part of the area where hackett fischer’s “distressed cavaliers and indentured servants” came from.

meanwhile (well, not really meanwhile ’cause the centuries are off), in cumbria up north on the border with scotland (from Albion’s Seed):

“In many cases the husband and wife both came from the same clan. In the Cumbrian parish of Hawkshead, for example, both the bride and groom bore the same last names in 25 percent of all marriages from 1568 to 1704.”

so, up north, cumbrians were marrying their paternal kin twenty-five percent of the time — presumably anywhere from first- to sixth-cousins or even farther out, who knows? but that twenty-five percent only includes paternal kin. who knows how frequently they married maternal kin in addition?

i know, i know. the centuries don’t match so these data sets aren’t really comparable. but trust me — this is a general pattern for england — greater inbreeding in the north and less in the south. i’ll have some follow up posts offering more proof for this phenomenon. promise!

previously: but what about the english? and cousin marriage rates amongst nineteenth century english and english jews and exogamous marriage in medieval england and invention of the modern world

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endogamy and genetic relatedness

this is just a short note — a little food for thought.

the following quote comes from catherine linley day’s FABULOUS ph.d. thesis, “Marriage Patterns in Two Wiltshire Parishes 1754-1914: Geographical Mobility, Consanguinity and Illegitimacy” [opens pdf]:

“In a theoretical isolated population of 500 people, after six generations all potential marriage partners would have been related to each other as 3rd cousins or closer (Fox 1967).”

the fox 1967 reference is to robin fox’s Kinship & Marriage: An Anthropological Perspective. i haven’t looked through fox’s book, yet, to see where linley day got this from.

in any case, it’s interesting to see how quickly endogamous mating patterns can lead to everyone in the population being quite related to one another (like in iceland or ashkenazi jews), genetically speaking. of course, no human population is totally isolated (right??), so you won’t find this exact scenario out in nature. but it’s interesting — and important — to keep in mind.

update 7/10 – calculating the inbreeding coefficient (see comments below):

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*update 07/11: john derbyshire’s found the source of this very informative map. hmmmm. for some strange reason i now seem to be associating the words “dark” and “horse” with the derb. (~_^)

don’t say i never gave you guys anything. (~_^) (no, i have no idea where the data came from!)

previously: size doesn’t matter

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libertarian crackers

nick land points out that it seems as though american libertarians tend to be of southern extraction — in other words, the descendants of those rustlin’ and fightin’ and inbreedin’ border reivers folks — and that they have that libertarian spirit because of their slight inbrededness. that makes a lot of sense! — and i’ve actually been thinking along those lines myself, too.

as a reminder, hackett fischer found that appalachia and areas further south were primarily settled by extended families/clans from the border areas of england-scotland, and that these folks had a looooong history of inter-clan (low scale) warfare. these northerners married their cousins or endogamously more than southern englanders did. and they brought aaaall these customs and traditions with them when they settled in the u.s.

the border reivers hadn’t been marrying their father’s brother’s daughter’s (fbd) for thousands of years like the arabs, so they weren’t tribal like the arabs. but they were clannish because they continued to marry relatively closely long after the christian church told them not to (probably something like the irish).

and being clannish means you don’t trust outsiders. and that includes THE GUBMENT.

i think it’s kinda funny that individuals from groups that are somewhat inbred (not as outbred as the southern english, but not as inbred as the chinese or arabs) and clannish — and must, therefore, be more related to their fellow family members than southern englanders and, thus, be less of individuals genetically speaking than southern englanders must be on the whole — feel as though they are very independent and individualistic persons. even though these sentiments (not liking the interference of outsiders) likely evolved in a clannish setting (i think).

for example, i noted this once before of taki of takimag. he once said:

The highly individualistic Greek is too self-seeking to submit easily to others’ dictates. His unruliness has helped him survive through the centuries of oppression, as well as to rise above adversity. But it has also made him unaware of the advantages of a communal spirit and true democratic attitudes. This has created a climate where cheating is a way of life, where the highest and lowest of citizens do not hesitate to use dishonesty, especially in politics.”

but the greek is NOT “highly individualistic.” what he is, and has been for probably a very long time, is quite genetically attached to his extended family, and so the greeks prefer their own extended families over unrelated extended families in all areas of life (thus the nepotism and the corruption) — and generally don’t trust anyone in THE GUBMENT! just like libertarian crackers.

it’s funny how these (what i think are) innate feelings of antipathy towards outsiders get interpreted by some of the holders of those feelings as being a streak of independence. it is independence in a way, but it’s independence from outsiders, not an individual indpendence like the english have which actually results in most or all of the individuals wanting to come together and form a government “of the people,” etc., etc.

disclaimer: pew tells me i’m a libertarian (not really, but i do sympathize), and i’m from one of the inbred peripheral groups of europe, so there you go — i’m practically living proof! (~_^)

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why mbd marriage amounts to less inbreeding than fbd marriage

in response to my post on why fbd marriage amounts to more inbreeding than mbd marriage (short answer: it results in more double-first cousin marriages), violet asks:

“I don’t understand why there can’t be double first cousins with mbd.”

good question. well, there certainly can be double-first cousin marriages in mbd societies, it’s just that the structure of mbd marriage doesn’t give the same push towards double-first cousin marriage as fbd marriage does.

what i should’ve done in the previous post on fbd (father’s brother’s daughter) marriage was to include diagrams of mbd (mother’s brother’s daughter) marriage along with the diagrams of fbd marriage, but to be honest i just got lazy (sorry!). so, without further ado, here is mbd marriage (you might want to have open the fbd marriage post at the same time):

ego (red triangle guy) marries his maternal first cousin, i.e. his mother’s brother’s daughter (mbd).

but who does ego’s brother (the triangle to the right of ego) marry? if he lives in a society in which mbd marriage is favored (china, for instance), and if there’s a female maternal cousin available, he’ll marry her (maybe/probably). in this case, that’s ego’s wife’s sister:

then what? well, in the next generation, unlike in fbd marriage, the kids of ego and his brother should NOT marry each other. the kids should marry their mothers’ brothers’ kids:

these kids are all first cousins, but they’re not double-first cousins (unlike in the fbd marriage scenario). the four kids do not share both sets of grandparents in common, whereas double-first cousins do.

also, you can see that there’s an additional party brought into this family tree — the yellow mom/aunt. she is not from ego’s patrilineage. she’s an outsider to some degree or another, and these wives that are brought in from the outside are why mbd marriage is often described as alliance building — different patrilineages build ties with one another.

so, the mbd marriage system doesn’t have the same push towards double-first cousin marriage as an fbd marriage system does. you can see this (i think) if you browse through the tables — there are more incidences of double-first cousin marriages recorded in fbd societies (arabs et al.) than in mbd societies (just about everybody else).

the reason any of this is good to know is because it is important to bear in mind that not all cousin marriage systems are the same — some result in more inbreeding or closer genetic relatedness between family members than others — and that should affect the evolution of “genes for altruism/other innate social aptitudes” in these populations.

previously: why fbd marriage amounts to more inbreeding than mbd marriage and tribes and types of cousin-marriage

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