Comparative characteristics of developing morphofunctional features of schoolchildren from different climatic and geographical regions.

OBJECTIVES: Adaptation processes in body of schoolchildren, along with study load and social factors, are determined by influence of climatic and geographical factors of residence region. This research has been undertaken to study the morphofunctional characteristics of schoolchildren at the age of 7-17 years. METHODS: The research involved 880 schoolchildren of both sexes in age from 7 to 17 years, studying in secondary school №22 in Pavlodar (Kazakhstan) and secondary school №7 in Kyzylorda (Kazakhstan). The Quetelet index of northern schoolchildren was within the norm but higher compared to southern peers. RESULTS: The Quetelet index was within the normal range for all schoolchildren, but higher among northerners. The indicator of the life index in the boys of the south was higher up to 10 years, then the adaptive possibilities of breathing decreased; in the girls in the north this indicator was higher in all periods, except for 8-9 years. The physical performance index (PWC170/kg) was higher in children from the southern region. CONCLUSIONS: This study revealed significant geographical differences in the morphofunctional development of children. The obtained data served allowed establishing the "Electronic map of schoolchildren's health" and indicated the need for systematic accounting of schoolchildren's health indicators for effective development of differentiated prevention programs.

Detection of genetic variations in the GDF9 and BMP15 genes in Kazakh meat-wool sheep.

Kazakh meat-wool sheep are of great interest because of the intrabreed multifetal type's high productivity of 140 %-160 %. Genes encoding growth differentiation factor-9 (GDF9) and bone morphogenetic protein 15 (BMP15) are promising candidates for studying sheep productivity, as they affect fertility in mammals, including sheep. Thus, the purpose of this study was to assess the fertility of the Kazakh meat-wool sheep breed based on GDF9 and BMP15 candidate genes of fecundity for the selection of animals with valuable genotypes. We selected 300 heads of the Kazakh meat-wool sheep breed from two populations for PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis, 15 of which were subsequently used for sequencing of exon regions of the GDF9 and BMP15 genes. The sheep populations were tested for G1 and G8 mutations of the GDF9 gene and B2 and B4 mutations of the BMP15 gene. The PCR-RFLP analysis revealed that 59 (19.7 %) of the 300 Kazakh meat-wool breed sheep were heterozygous carriers of the G1 mutation (genotype AG) of the GDF9 gene, and sequencing analysis supported these results. The comparative phylogenetic analysis showed a clear separation of Kazakh meat-wool sheep wild types and carriers of the G1 mutation. This mutation was reported to have a relationship with the animals' litter size in other sheep breeds. For this reason, similar relationships should be investigated in Kazakh meat-wool sheep. However, G8, B2, and B4 mutations were not detected among the studied animal populations, showing that these mutations are not characteristic of the Kazakh meat-wool sheep breed.