TY - JOUR

T1 - Marital Structure, Genetic Fitness, and the GJB2 Gene Mutations among Deaf People in Yakutia (Eastern Siberia, Russia)

AU - Romanov, G. P.

AU - Barashkov, N. A.

AU - Teryutin, F. M.

AU - Lashin, S. A.

AU - Solovyev, A. V.

AU - Pshennikova, V. G.

AU - Bondar, A. A.

AU - Morozov, I. V.

AU - Sazonov, N. N.

AU - Tomsky, M. I.

AU - Dzhemileva, L. U.

AU - Khusnutdinova, E. K.

AU - Posukh, O. L.

AU - Fedorova, S. A.

N1 - Publisher Copyright: © 2018, Pleiades Publishing, Inc.

PY - 2018/5/1

Y1 - 2018/5/1

N2 - Autosomal recessive deafness type 1A (DFNB1A) caused by mutations in the GJB2 gene (Cx26) is the main cause of nonsyndromic hearing impairment in many populations worldwide. It is considered that widespread prevalence of DFNB1A can be due to the long tradition of intermarriages between deaf people (assortative marriages) combined with their increased social adaptation and genetic fitness after widespread introduction of sign language. For the first time, the data on mating structure and reproduction of deaf people living in Yakutia (Eastern Siberia, Russia) are presented in comparison with contribution of the GJB2 gene mutations to the etiology of hearing impairment. The relative fertility of deaf people compared to their hearing siblings is 0.78 (mean number of children 1.76 ± 0.10 and 2.24 ± 0.09 to deaf and their hearing siblings, respectively, p = 0.0018). The rate of assortative marriages among deaf people is 77.1% (81 of 105 marriages). Biallelic mutations in the GJB2 gene were found in 42.2% (43 of 102) of examined deaf people, which corresponded to diagnosis DFNB1A for these patients. A comparison of deaf marital partners by GJB2 status revealed a proportion of noncomplementary marriages (24%) in which hearing loss in both partners was caused by the presence of biallelic GJB2 gene mutations resulting in the birth of only deaf children in such couples. Thus, the set of obtained data including a relatively high genetic fitness (expressed as relative fertility) of deaf people in Yakutia in combination with a high rate of assortative marriages among them and high incidence of DFNB1A indicates a possible weakening of selection against such trait as “deafness” and a possible increase in the frequency of GJB2 mutant alleles in subsequent generations.

AB - Autosomal recessive deafness type 1A (DFNB1A) caused by mutations in the GJB2 gene (Cx26) is the main cause of nonsyndromic hearing impairment in many populations worldwide. It is considered that widespread prevalence of DFNB1A can be due to the long tradition of intermarriages between deaf people (assortative marriages) combined with their increased social adaptation and genetic fitness after widespread introduction of sign language. For the first time, the data on mating structure and reproduction of deaf people living in Yakutia (Eastern Siberia, Russia) are presented in comparison with contribution of the GJB2 gene mutations to the etiology of hearing impairment. The relative fertility of deaf people compared to their hearing siblings is 0.78 (mean number of children 1.76 ± 0.10 and 2.24 ± 0.09 to deaf and their hearing siblings, respectively, p = 0.0018). The rate of assortative marriages among deaf people is 77.1% (81 of 105 marriages). Biallelic mutations in the GJB2 gene were found in 42.2% (43 of 102) of examined deaf people, which corresponded to diagnosis DFNB1A for these patients. A comparison of deaf marital partners by GJB2 status revealed a proportion of noncomplementary marriages (24%) in which hearing loss in both partners was caused by the presence of biallelic GJB2 gene mutations resulting in the birth of only deaf children in such couples. Thus, the set of obtained data including a relatively high genetic fitness (expressed as relative fertility) of deaf people in Yakutia in combination with a high rate of assortative marriages among them and high incidence of DFNB1A indicates a possible weakening of selection against such trait as “deafness” and a possible increase in the frequency of GJB2 mutant alleles in subsequent generations.

KW - assortative marriages

KW - deafness

KW - GJB2 gene

KW - relative fertility

KW - Yakutia

UR - http://www.scopus.com/inward/record.url?scp=85047237520&partnerID=8YFLogxK

U2 - 10.1134/S1022795418050071

DO - 10.1134/S1022795418050071

M3 - Article

AN - SCOPUS:85047237520

VL - 54

SP - 554

EP - 561

JO - Russian Journal of Genetics

JF - Russian Journal of Genetics

SN - 1022-7954

IS - 5

ER -