In silico structural, functional and pathogenicity evaluation of a novel mutation: an overview of HSD3B2 gene mutations

Gene. 2012 Jul 25;503(2):215-21. doi: 10.1016/j.gene.2012.04.080. Epub 2012 May 8.

Abstract

Mutations of 3 beta hydroxysteroid dehydrogenase type II (HSD3B2) gene result in different clinical consequences. We explain a patient who demonstrated a salt wasting form of 3βHSD deficiency in infancy. Signs of hyponatremia and hyperkalemia were recognized in the infant with ambiguous genitalia and perineal hypospadias. The 46,XY male was genotyped by direct sequencing of HSD3B2 gene. Steroid profiles showed elevated concentration of 17 hydroxyprogesterone, and decrease in concentration of cortisol, and testosterone. Dehydroepiandrotone (DHEA) to androstenedione ratio had 6 fold increases. Direct sequencing of the patient revealed homozygous missense A82P mutation in exon 3. This mutation was confirmed by segregation analysis of the parents. Bioinformatic tools were used for in silico structural and functional analyses. Also, the pathological effect of the mutation was validated by different software. Alanine is a conserved amino acid in the membrane binding domain of the enzyme and proline substitution was predicted to destabilize the protein. This report may highlight the importance of the screening programs of the disorder in Iran.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Hyperplasia, Congenital / genetics*
  • Amino Acid Sequence
  • Base Sequence
  • Computational Biology
  • Disorders of Sex Development
  • Genotype
  • Humans
  • Infant, Newborn
  • Male
  • Molecular Sequence Data
  • Mutation, Missense*
  • Polymorphism, Single Nucleotide
  • Progesterone Reductase / chemistry
  • Progesterone Reductase / deficiency
  • Progesterone Reductase / genetics*
  • Progesterone Reductase / metabolism
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Software

Substances

  • 3 beta-hydroxysteroid dehydrogenase type II
  • Progesterone Reductase