

CAGn polymorphic locus of the androgen receptor (AR) gene in Klinefelter syndrome patients
https://doi.org/10.25557/2073-7998.2024.12.58-66
Abstract
Klinefelter syndrome (KS) is the most common gonosomal aneuploidy caused by the presence of one, rarely 2-4 additional X chromosomes in the karyotype in male patients. The phenotypic variability of the disease may be associated with the influence of the cytogenetic variant of KS, as well as other genetic and epigenetic factors. A number of studies have established the influence of parental origin and inactivation of the X chromosome, as well as its genes and their variants, in particular the CAG polymorphic locus of the androgen receptor (AR) gene. However, the frequency of individual allelic variants and genotypes for this polymorphic locus have not been studied in KS patients. In this study, the CAG polymorphic locus of the AR gene was analyzed in 222 KS patients. The number of trinucleotide repeats was determined using the PCR-based AFPL (amplified fragment lengths polymorphism) method. The number of CAG repeats varied from 14 to 32, the average number was 22.3 ± 2.7. In the studied sample, 59 patients were homozygous, 163 patients were heterozygous at this locus. In both groups, the frequent alleles contained 20-25 CAG repeats, the median was 22. A statistically significant (p < 0.05) difference was found in the allelic frequency of the most common variant of CAGn, n=21 between homozygotes and heterozygotes. The revealed difference for CAGn polymorphic locus of the AR gene between homozygous and heterozygous KS patients can be explained by possible differences in the frequency of sex chromosomes non-disjunction in the germ cells of their parents, which requires further investigation.
About the Authors
V. B. ChernykhRussian Federation
Vyacheslav B. Chernykh
1, Moskvorechie st., Moscow, 115478;
1, Ostrovityanova st., Moscow, 117513
O. A. Solovova
Russian Federation
1, Moskvorechie st., Moscow, 115478
T. M. Sorokina
Russian Federation
1, Moskvorechie st., Moscow, 115478
M. I. Shtaut
Russian Federation
1, Moskvorechie st., Moscow, 115478
M. V. Andreeva
Russian Federation
1, Moskvorechie st., Moscow, 115478
D. A. Bespalyuk
Russian Federation
11, Dm. Ulyanova st., Moscow, 117292
A. A. Stepanova
Russian Federation
1, Moskvorechie st., Moscow, 115478
E. A. Bliznets
Russian Federation
1, Moskvorechie st., Moscow, 115478
N. V. Oparina
Russian Federation
2, Abrikosovsky per., Moscow, 119991
N. V. Shilova
Russian Federation
1, Moskvorechie st., Moscow, 115478
O. A. Schagina
Russian Federation
1, Moskvorechie st., Moscow, 115478
A. V. Polyakov
Russian Federation
1, Moskvorechie st., Moscow, 115478
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Review
For citations:
Chernykh V.B., Solovova O.A., Sorokina T.M., Shtaut M.I., Andreeva M.V., Bespalyuk D.A., Stepanova A.A., Bliznets E.A., Oparina N.V., Shilova N.V., Schagina O.A., Polyakov A.V. CAGn polymorphic locus of the androgen receptor (AR) gene in Klinefelter syndrome patients. Medical Genetics. 2024;23(12):58-66. (In Russ.) https://doi.org/10.25557/2073-7998.2024.12.58-66