Study of Ras/MAPK pathway gene variants in Chilean patients with Cryptorchidism

Andrology. 2018 Jul;6(4):579-584. doi: 10.1111/andr.12501. Epub 2018 May 11.

Abstract

Cryptorchidism is one of the most common congenital disorders in boys, and several genetic, hormonal, and environmental factors have been proposed as possible causes for this genitourinary defect. Genetic factors have been intensively searched, but relatively few pathogenic variants have been described. Cryptorchidism is a frequent finding in patients with RASopathies, a group of syndrome caused by mutations in genes of the Ras/MAPK pathway. Our aim was to determine whether patients with isolated cryptorchidism (IC) exhibit Ras/MAPK pathway gene variants associated with RASopathies. Two hundred thirty-nine patients with IC were recruited after orchidopexy. Determination of Ras/MAPK pathway gene variants was performed by high-resolution melting (HRM) analysis followed by sequencing. Restriction or allele-specific amplification assay was applied to (i) variant confirmation; (ii) search in healthy controls; and (iii) segregation analysis. Controls correspond to 100 healthy Chilean adults without a history of cryptorchidism. Molecular analysis showed one synonymous substitution (BRAF_p.Q456Q) in two patients and four missense substitutions (SOS1_ p.R497Q, BRAF_ p.F595L, NRAS_ p.T50I, and MAP2K2_ p.Y134C) in five patients. Our results suggest that some patients with isolated cryptorchidism, but with no evidence of dysmorphic features suggestive of RASopathies, may harbor Ras/MAPK pathway gene alterations.

Keywords: Cryptorchidism; Nucleotide variants; RASopathies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Child
  • Child, Preschool
  • Chile
  • Cryptorchidism / genetics*
  • GTP Phosphohydrolases / genetics*
  • Genetic Variation
  • Humans
  • Infant
  • MAP Kinase Kinase 2 / genetics*
  • Male
  • Membrane Proteins / genetics*
  • Mitogen-Activated Protein Kinases / genetics
  • Proto-Oncogene Proteins B-raf / genetics*
  • SOS1 Protein / genetics*
  • Signal Transduction / physiology
  • ras Proteins / genetics

Substances

  • Membrane Proteins
  • SOS1 Protein
  • MAP2K2 protein, human
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf
  • Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase 2
  • GTP Phosphohydrolases
  • NRAS protein, human
  • ras Proteins