Case report of mild TCIRG1-associated autosomal recessive osteopetrosis in Vietnam

Am J Med Genet A. 2022 Oct;188(10):3096-3099. doi: 10.1002/ajmg.a.62897. Epub 2022 Aug 1.

Abstract

Autosomal recessive osteopetrosis (ARO) is a group of disease characterized by osteoclast dysfunction inhibiting bone resorption and bone turnover, with TCIRG1-associated ARO being more common leading to autosomal recessive infantile malignant osteopetrosis (OPTB1, MIM entry number # 259700). While most patients with TCIRG1-associated osteopetrosis present a malignant clinical course and shortened lifespan, a few cases of non-malignant TCIRG1-associated osteopetrosis have been reported. 24-year-old female patient came to us with limp gait, hip pain in both sides, and severe stiffness. She had suffered many fractures, bilateral hip osteoarthritis, right leg was 2 cm shorter compared with left leg. Whole Exome Sequencing was conducted, the result and subsequent Sanger's sequencing shown the patient had a compound heterozygous genotype at TCIRG1 (c.1194dup, p.Gly399ArgTer and c.334G>A, p.Gly112Arg), these two variants found were not previously reported. Sanger's sequencing revealed two other siblings whom suffer the same disorder had similar genotype to the proband; the parents were found to be heterozygous. This is the first case of TCIRG1-associated osteopetrosis reported in Vietnam and one of the few cases of nonmalignant TCIRG1-associated osteopetrosis, in which detailed clinical and genetic work-up were performed.

Keywords: TCIRG1; hip osteoarthritis; osteopetrosis; total hip replacement.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Female
  • Humans
  • Mutation
  • Osteopetrosis* / diagnosis
  • Osteopetrosis* / genetics
  • Siblings
  • Vacuolar Proton-Translocating ATPases* / genetics
  • Vietnam
  • Young Adult

Substances

  • TCIRG1 protein, human
  • Vacuolar Proton-Translocating ATPases