Novel and Novel De Novo Mutations in NTRK1 Associated With Congenital Insensitivity to Pain With Anhidrosis: A Case Report

Congenital insensitivity to pain with anhidrosis (CIPA) is a very rare autosomal recessively inherited disorder. The main clinical features of the disorder consist of absence of reactions to noxious stimuli and inability to sweat under any conditions. In this case report, a 3-year-old Chinese boy diagnosed with CIPA presented with the core features of CIPA, including insensitivity to noxious stimuli, self-mutilation, inability to sweat, and developmental delay. Clinical and genetic analyses were conducted on the affected boy. Sequencing analysis revealed an inherited novel mutation, c.1635G>C, and a novel de novo mutation, c.2197G>A, in the NTRK1 gene. In silico studies suggested that the mutations described are detrimental to the function of the protein encoded by the NTRK1 gene. The two novel mutations described here widen the genetic spectrum of CIPA, and this knowledge will benefit studies addressing this disease and pain medicine in the future.