Brief communication: Effect of nomadic subsistence practices on lactase persistence associated genetic variation in Kuwait

Abstract

Lactase persistence (LP)-the ability to digest lactose in adulthood-is paradigmatic of Holocenic dietary change affecting the evolutionary trajectory of specific populations. Kuwait represents one location of high LP where the variation in associated genomic regions has not been examined. Here, we present new sequence data from a 427 bp amplicon 14 kb upstream of the LCT (lactase) gene for two Bedouin tribal populations, the Ajman and Mutran. We estimate the frequency of known LP associated alleles and discuss the impact of nomadic-pastoralism on the associated genetic variation. We observe high frequency (56% on average) of the -13,915*G allele in both tribes, which is consistent with the high prevalence of LP in Kuwait. Whilst LP associated alleles occur in Kuwait at a similar frequency to other regional populations, we suggest that the -13,915*G allele frequency among the Kuwaiti Bedouin may be higher than among non-Bedouin Kuwaitis, possibly due to greater historical reliance on milk consumption or genetic drift.

The historical spread of Arabian Pastoralists to the eastern African Sahel evidenced by the lactase persistence −13,915*G allele and mitochondrial DNA

“…The relatively low frequency of the LP variant and low differentiation between pastoralists and farmers in Central Asia might be consistent with the higher consumption of fermented milk products, hence reducing selective pressure for LP. Conversely, low consumption of sour milk has been reported in the Bedouins in Arabia (Thesiger, 1959), as well as in the Baggara (Adam, 2012), and the effects of subsistence practices on the genetic differentiation between pastoralists and farmers are more marked in these populations (Hill et al, 2013).…”