Lactose intolerance and its association with the exogamy degree among the population of eastern Ukraine

Abstract

Aim. The aim of our study was to evaluate the relationship between exogamy degree and lactose assimialation among the population of Eastern Ukraine in the Kharkiv region. Methods. The analysis included information on consumption and assimilation of milk and dairy products by 733 people aged from 14 to 79 years were. Statistical analysis included Shapiro-Wilk test, Pearson fitting (χ2) criterion and Spearman’s correlation analysis. Results. The lactose tolerance (LT) phenotype was found in 69.5%, whereas lactose intolerance (LI) – in 8.8% (from 3.5% to 24.1% in different age groups). In the age group 30-39 years: LI frequency was 24.1% being 2.5-6 times higher than in other groups. The exogamy degree of parents (EDP) showed in the group aged from 30 to 39 years the first EDP was 15.4%, being 1.4-2.5 times less (p = 0,05) than in other groups. Among people with bone marrow disorders the proportion of people with the first and second EDP was 60.9%, being 2.1 to 6.0 times higher than in other groups. Reduced EDP or increased inbreeding level causes the similarity of the chromosomes and affects the density of contact points between them during meiosis, level of recombination can be increased and associated with multifactorial traits. Conclusions. The results can be explained by the effect of the inbreeding level reduction in the presence of a high level of exogamy of parents, which causes high genetic diversity.
 Keywords: lactose intolerance, lactose tolerance, exogamy degree of parents, single nucleotide polymorphisms 13910C-T and 22018G-A, gene МСМ6.

Genetic aspects of lactase persistence in different ethnic groups

“…Lactose intolerance is the risk factor for fractures and osteoporosis but is also could associated with gastrointestinal pathologies. Our results obtained previously indicate that patients with CTGA genotype had osteoporosis and disorders of the gastrointestinal tract, such as gastritis (43 %), peptic ulcer (29 %), stomach cancer (12.5 %) and others [6].…”

“…The tendency for associative marriages has the effect of increasing the inbreeding level. It leads to a decrease in genetic diversity, an increase in the number of similar loci in chromosomes during conjugation, and thus to an increase in the recombination processes associated with chromosome rearrangements, and consequently to a decrease the number of homozygotes [13].The results of our previous studies have shown that people who consumed milk and dairy products in childhood and decreased this ability with age had heterozygous genotypes: CTGA of SNPs-13910C-T (rs4988235) and 22018G-A (rs182549) of MCM6gene [6]. Therefore, the results of this study are consistent with previous findings.…”

“…The survey on the consumption and assimilation of cow's milk and dairy products was conducted on a scale: from the 1st-always consumed to the 3rd -never consumed. The method of exogamy degree estimation was described previously [6]…”

Study of the lactose intolerance genetic aspects among the population and patients with hip fracture in eastern Ukraine

“…According to our results, in this group the lowest value of persons with the lowest parents' exogamy degree was noted. As we have shown earlier, parameters of persons exogamy degree may affect the frequency of genetic recombination [16].…”