Rafael Loch Batista1, Andresa De Santi Rodrigues2, Aline Zamboni Machado2, Mirian Yumie Nishi2, Flávia Siqueira Cunha2, Rosana Barbosa Silva2, Elaine M F Costa2, Berenice B Mendonca2, Sorahia Domenice2. 1. Laboratório de Hormônios e Genética Molecular (LIM/42), Unidade de Endocrinologia do Desenvolvimento, Disciplina de Endocrinologia e Metabologia do Hospital das Clınicas, Faculdade de Medicina, Universidade de São Paulo, Av. Dr. Eneas de Carvalho Aguiar, 155, 7 andar, São Paulo, SP CEP 05403-900, Brasil. 2. Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42, Hospital das Clínicas, Disciplina de Endocrinologia e Metabologia, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brasil.
Abstract
BACKGROUND: Androgen insensitivity syndrome (AIS) is the most frequent etiology of 46,XY disorders of sex development (DSDs), and it is an X-linked disorder caused by mutations in the androgen receptor (AR) gene. AIS patients present a broad phenotypic spectrum and individuals with a partial phenotype present with different degrees of undervirilized external genitalia. There are more than 500 different AR gene allelic variants reported to be linked to AIS, but the presence of somatic mosaicisms has been rarely identified. In the presence of a wild-type AR gene, a significant degree of spontaneous virilization at puberty can be observed, and it could influence the gender assignment, genetic counseling and the clinical and psychological management of these patients and the psychosexual outcomes of these patients are not known. CASE PRESENTATION: In this study, we report two patients with AR allelic variants in heterozygous (c.382G>T and c.1769-1G>C) causing a partial AIS (PAIS) phenotype. The first patient was raised as female and she had undergone a gonadectomy at puberty. In both patients there was congruency between gender of rearing and gender identity and gender role. CONCLUSIONS: Somatic mosaicism is rare in AIS and nonsense AR variant allelic can cause partial AIS phenotype in this situation. Despite the risk of virilization and prenatal androgen exposure, the gender identity and gender role was concordant with sex of rearing in both cases. A better testosterone response can be expected in male individuals and this should be considered in the clinical management.
BACKGROUND: Androgen insensitivity syndrome (AIS) is the most frequent etiology of 46,XY disorders of sex development (DSDs), and it is an X-linked disorder caused by mutations in the androgen receptor (AR) gene. AISpatients present a broad phenotypic spectrum and individuals with a partial phenotype present with different degrees of undervirilized external genitalia. There are more than 500 different AR gene allelic variants reported to be linked to AIS, but the presence of somatic mosaicisms has been rarely identified. In the presence of a wild-type AR gene, a significant degree of spontaneous virilization at puberty can be observed, and it could influence the gender assignment, genetic counseling and the clinical and psychological management of these patients and the psychosexual outcomes of these patients are not known. CASE PRESENTATION: In this study, we report two patients with AR allelic variants in heterozygous (c.382G>T and c.1769-1G>C) causing a partial AIS (PAIS) phenotype. The first patient was raised as female and she had undergone a gonadectomy at puberty. In both patients there was congruency between gender of rearing and gender identity and gender role. CONCLUSIONS: Somatic mosaicism is rare in AIS and nonsense AR variant allelic can cause partial AIS phenotype in this situation. Despite the risk of virilization and prenatal androgen exposure, the gender identity and gender role was concordant with sex of rearing in both cases. A better testosterone response can be expected in male individuals and this should be considered in the clinical management.
Entities:
Keywords:
46,XY disorders of sex development (DSD); androgen insensitivity syndrome; androgen receptor gene; gender assignment; heterozygous X-linked mutations; somatic mosaicism