Lactase persistence in Britain

Lactase persistence-related genetic variant: population substructure and health outcomes:

Lactase persistence is an autosomal-dominant trait that is common in European-derived populations. A basic tendency for lactase persistence to increase from the southeast to the northwest across European populations has been noted, but such trends within countries have not been extensively studied. We genotyped the C/T-13910 variant (rs4988235) that constitutes the putatively causal allele for lactase persistence (T allele representing persistence) in a general population sample of 3344 women aged 60-79 years from 23 towns across Britain. We found an overall frequency of 0.253 for the C (lactase non-persistence) allele, but with considerable gradients of decreasing frequency from the south to the north and from the east to the west of Britain for this allele. Daily sunlight was positively related to C...allele prevalence. However, sunlight exposure and latitude are strongly correlated, and it was not possible to identify which is the primary factor statistically underlying the distribution of lactase persistence. The C/T-13910 variant...was not related to drinking milk or bone health (although drinking milk itself was protective of bone health), and was essentially unrelated to a wide range of other lifestyle, health and demographic characteristics. One exception was general health being rated as being poor or fair, for which there was an odds ratio of 1.38...for women homozygous for the C allele; on adjustment for latitude and longitude of place of birth, this attenuated to 1.19...The lactase persistence variant could contribute to the examination of data for the existence of, and then statistical control for, population substructure in genetic association studies.

Interesting. I can't help but point out that the frequency of the LP allele follows the gradient of the decrease in Anglo-Saxon ancestry by any measure. This is relevant because the area focused around Jutland is where the modal frequency of the LP allele exists. So this could just be an artifact of demographic history.

H/T Dienekes

Related: Other posts on lactase persistence.

Tags

More like this

As you know lactase persistence (LP), which confers the ability to digest lactose sugar as an adult, is an evolutionarily recent development. On the order of 1/3 of the human population exhibits LP, due to a variety of genetic mutations which seem to arise in the cultural background of the…
Convergent adaptation of human lactase persistence in Africa and Europe: A SNP in the gene encoding lactase (LCT) (C/T-13910) is associated with the ability to digest milk as adults (lactase persistence) in Europeans, but the genetic basis of lactase persistence in Africans was previously unknown.…
Over the past few weeks I've talked about the relationship of genes & biology to culture. First I noted the likely impact of the evolutionary arms race between our adaptive immune system and plagues & endemic infectious diseases upon the course of human history. Second, I pointed to the…
Update: Another post on this topic at my other blog. A few days ago I pointed to a new paper, Evidence of Still-Ongoing Convergence Evolution of the Lactase Persistence T-13910 Alleles in Humans. Knowing my interest in the topic you might assume that I would be "all over this." Well, I finally…

That's interesting. So that would mean that "Celtic"/Iberian descended people in Ireland and Wales don't tolerate milk as well as the more Germanic people in the south and east? Did Ireland historically not have a dairy culture?

Ok, I assumed British Isles. Still the point remains the same as to whether Celtic peoples have less of a dairy culture than Germanic ones.

Much of N. Britain, especially Wales and Scotland, is so barren it's unsuitable for dairy farming. Glasgow is said to have exceptionally poor life expectancy. Could this be due to a dislike of, or an inability to properly metabolise, the intake of lactose?

I don't understand why it is so dangerous to say that lactose persitance developed in scandinavia proper, and is one of the reasons for the germanic expansion.

The germanic package was dairy farming together with iron and wooden technology.

This meant that they could clear forrests that other people could not, in that they could use the leaves of the trees as fodder and live off the milk and meat, until the ecology of the soil was good enough for agriculture, and the roots had rotted away.

What most likely happened during the Volkswanderungen, was that scandinavian milkdrinkers went seraching for forrests where few people lived.

The comments have me confused. The second highlight in the abstract says the non-persistence allele decreases to the northwest of Britain; persistence must increase to northwest. Do the people of the southeast have greater Germanic ancestry and lower frequency of persistence?