Least common cause of ambiguous genitalia in female genotype:
Ans. C. Fetal steroid sulphatase deficiencyRef: Sperojf, 9th/ed, pll9ExplanationPlacental sulfatase deficiency# There is an X-linked metabolic disease characterized by a placental sulfatase deficiency in the syncytiotrophoblast, and postnatally, ichthyosis, occurring in about 1 in 2000-3000 newborn males.# Patients with the placental sulphatase disorder are unable to hydrolyze DHAS or 16a-hydroxy- DHAS, and, therefore, the placenta cannot form normal amounts of estrogen.# A deficiency in placental sulphatase is usually discovered when patients go beyond term and are found to have extremely low estriol levels and no evidence of fetal distress.# All newborn children, with a few exceptions, have been male.# The steroid sulfatase X-linked recessive ichthyosis locus (the steroid sulphatase gene) has been mapped to the distal short arm portion of the X chromosome.# Family history of scaling in males (as well as repeated postdate pregnancies) should prompt a consideration for prenatal diagnosis.WT1 gene# The VVT2 gene is named after the Wilms' tumor nephroblastoma because it is one of the genes on chromosome 11 deleted in patients with this tumor. Mutant mice lacking WT2 fail to develop kidneys and gonads.# WT1 mutations, however, could not be detected in 25 patients with a congenital absence of the uterus and vagina, indicating that WT1 may be necessary for normal renal and gonadal development, but not for early Mullerian duct development.
21 hydroxylase deficiency
11 hydroxylase deficiency
Fetal steroid sulphatase deficiency
WT1 gene
Sex Intersexuality