Humangenetik und Embryologie

Disorders of Sex development 46, XY SRY (-) vs. 46, XX SRY (+): About 2 Cases

Abstract

Mame Venus Gueye1,2*, Ndiaye Arame1,3, Diop Ndiaga1,2, Diallo Mama Sy1,2, Gueye Fatou Diop1,3, Diallo Adji Dieynaba1,3, Diallo AbdoulayeSéga1,2, Ngom Aminata Issa, Ndiade Amadou4, Diatta Ange Lucien5, Diatta Robert6 and Faye Omar1,2

Introduction: Disorders or anomalies of Sex differentiation or Development (DSD),are congenital conditions during which the chromosomal, gonadal, and anatomical sexes are atypical. Cytogenetics and molecular genetics are essential in the classification of these variations by Karyotyping and searching for variants. Thus, we selected 2 patients of female civil status among those sent for diagnosis of a DSD and aim to do karyotype but also to verify the presence of the steroid genic region of the Y chromosome (SRY) by Polymerase Chain Reaction (PCR).

Materials and methods: We proceeded to a peripheral venous blood sample in a heparinized tube for the karyotype, and another tube with Ethylene Diamine Tetra Acetic acid (EDTA) for DNA extraction to search for the presence of the SRY gene by PCR.

Results: At the karyotype, the first patient had a formula 46, XY and the second a formula 46, XX. After PCR amplification of the SRY gene and electrophoretic migration on agarose gel, patient the first patient was SRY (+) and the second SRY (-).

Conclusion: Cytogenetics has a fundamental place in the classification of disorders of sexual development. Our patients could be classified as 46, XY DSD, as 46, XX DSD. The search of the SRY gene by PCR constitutes a good starting point in the molecular search for the etiological diagnosis of these abnormalities or variations in sexual differentiation.