Archiver > GENEALOGY-DNA > 2009-04 > 1240758664

Subject: [DNA] PubMed abstract: lactase persistence within Britain
Date: Sun, 26 Apr 2009 11:11:04 EDT

Eur J Hum Genet. 2009 Mar;17(3):357-67. Epub 2008 Sep 17.

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

Smith GD, Lawlor DA, Timpson NJ, Baban J, Kiessling M, Day IN, Ebrahim S.

MRC Centre for Causal Analyses in Translational Epidemiology, Department of
Social Medicine, University of Bristol, Bristol, UK.

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 (non-persistence)
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 (rs4988235) 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 (1.04, 1.84) for women homozygous
for the C allele; on adjustment for latitude and longitude of place of
birth, this attenuated to 1.19 (0.87, 1.64). 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.

Publication Types:
Research Support, Non-U.S. Gov't

PMID: 18797476 [PubMed - indexed for MEDLINE]

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