Transferability of the PRS estimates for height and BMI obtained from the European ethnic groups to the Western Russian populations

Genetic data plays an increasingly important role in modern medicine. Decrease in the cost of sequencing with subsequent increase in imputation accuracy, and the accumulation of large amounts of high-quality genetic data enable the creation of polygenic risk scores (PRSs) to perform genotype-phenotype associations. The accuracy of phenotype prediction primarily depends on the overall trait heritability, Genome-wide association studies cohort size, and the similarity of genetic background between the base and the target cohort. Here we utilized 8,664 high coverage genomic samples collected across Russia by "Evogen", a Russian biomedical company, to evaluate the predictive power of PRSs based on summary statistics established on cohorts of European ancestry for basic phenotypic traits, namely height and BMI. We have demonstrated that the PRSs calculated for selected traits in three distinct Russian populations, recapitulate the predictive power from the original studies. This is evidence that GWAS summary statistics calculated on cohorts of European ancestry are transferable onto at least some ethnic groups in Russia.

[EVALUATION OF THE MEDICAL AND ECONOMIC EFFICIENCY OF NON-INVASIVE PRENATAL TESTING IN MOSCOW]

to evaluate the medical and economic efficiency of prenatal diagnostics of fetal chromosomal abnormalities (CA) in pregnant women in Moscow using a non-invasive prenatal test (NIPT) as a second-line model. A comparative analysis of the medical and economic efficiency of standard prenatal screening and prenatal screening with NIPT in groups of pregnant women, registered in Moscow, with high and medium fetal CA risk was carried out. Analysis was based on the number of children born with CA and the costs of medical care (direct costs) and social payments (indirect costs), calculated for both scenarios. Following standard prenatal screening 111 children with CA would be born, following prenatal screening with NIPT - only 26. Including NIPT in prenatal diagnostics increases direct costs by 299.97 million rubles and reduces annual indirect costs from 61.19 to 28.95 million rubles. Starting from the 13th year of using NIPT the estimated effect of reducing indirect costs would exceed direct costs. NIPT in prenatal diagnostics can increase the detection of fetal CA and reduce indirect costs. Assessing the indirect costs in economic efficiency enhances the accuracy of the estimate.

Guidelines for genetic testing of healthy adults who deposit samples and related data in bioresource collections and biobanks

Currently, a significant part of research in the fields of human and medical genetics is carried out using tissue samples, genealogical, population, medical and personal data. Their use is of particular relevance in the “genome era”, since only joint analysis of genomic data and health status of the population is crucial for understanding how genes are associated with health and disease. Genetic studies of adults without symptoms of diseases are carried out to obtain data on a possible predisposition to multifactorial diseases, to establish the carrier status of autosomal recessive mutations as part of preconception care and to assess individual sensitivity to drugs. In addition, healthy individuals can be tested to detect an inherited disease at presymptomatic stage. This situation increasingly emphasizes the importance of storing data on genome sequencing or any other patient tests for subsequent data reanalysis, as well as their safety, including biosamples from an individual and one’s family. The review article, based on international experience, summarizes guidelines for genetic testing of healthy individuals. The options for storing biological samples and related data are considered.

[Twin reversed arterial perfusion syndrome in the monochorionic diamniotic placenta with the development of an acardiac fetus]

The article describes an acardiac fetus in a patient with monochorionic diamniotic twin pregnancy with reversed arterial perfusion syndrome at 30 weeks' gestation. It gives postmortem fetal computed tomographic and pathoanatomic data. Microarray of acardiac fetal tissues revealed that there was deletion of chromosome 19 - arr [hg19] 19p13.3q11 (260,911-23,005,001) x1; size, 23 Mbp; the signal level in about 30% of fetal tissue cells containing deletion.

[Genetic ecological monitoring in human populations: heterozygosity, mtDNA haplotype variation, and genetic load]

Yu. P. Altukhov suggested that heterozygosity is an indicator of the state of the gene pool. The idea and a linked concept of genetic ecological monitoring were applied to a new dataset on mtDNA variation in East European ethnic groups. Haplotype diversity (an analog of the average heterozygosity) was shown to gradually decrease northwards. Since a similar trend is known for population density, interlinked changes were assumed for a set of parameters, which were ordered to form a causative chain: latitude increases, land productivity decreases, population density decreases, effective population size decreases, isolation of subpopulations increases, genetic drift increases, and mtDNA haplotype diversity decreases. An increase in genetic drift increases the random inbreeding rate and, consequently, the genetic load. This was confirmed by a significant correlation observed between the incidence of autosomal recessive hereditary diseases and mtDNA haplotype diversity. Based on the findings, mtDNA was assumed to provide an informative genetic system for genetic ecological monitoring; e.g., analyzing the ecology-driven changes in the gene pool.