First Bosnian study of LCT -13910C>T and -22018G>A single nucleotide polymorphisms associated with adult-type lactose intolerance

Objectives: It is suggested, that over the last 1x104 years most ancient Europeans, have not been able to digest milk as adults. Lactose tolerance (lactase persistence) is an example of convergent evolution due to strong selective pressure resulting from shared cultural traits-animal domestication and adult milk consumption. This phenotype varies widely in humans, as a function of ethnicity. Recent reports have identified that a genetic polymorphisms -13910C>T and -22018G>A of LCT gene are closely associated with lactase persistence (LP) and lactase non-persistence (LNP) phenotypes. We sought to assess the prevalence of 13910C>T and -22018G>A variants of LCT gene in Bosnian subjects. Methods: The subjects of the study consisted of 151 unrelated subjects from Bosnia and Herzegovina (60 males and 91 females). The mean age of the study sample was 48.0±16.4) years. PCR-RFLP was used to study of genotype and allele distribution. Data were analyzed using the Stat View computer software version 5.0 (SAS Institute Inc. Cary, NC, USA). Electronic databases including Medline and Embase were searched from 1995 to February 2017. Results: The genotypes linked to the LP phenotype were found in 74 (41.0%) of the 151 subjects. The frequency of -13910T and -22018A alleles of LCT gene was 24.8% and 24.5%, respectively. The CC/GG genotype, related to LNP was found in 77 (51.0%) individuals. Conclusion: In studied European populations we observed a linear, gradually increasing trend in the frequency of -13910T allele from South to North (Pearson’s test: 0.5728 , P-value<0.001 ), and Bosnian population perfectly fits into this pattern. Keywords: LPH-1, lactase persistence, lactase non-persistance, population genetics