A Novel Mutation in TMPRSS15 Gene Causes a Severe Form of Congenital Enterokinase Deficiency

Congenital enterokinase deficiency is a rare autosomal recessive disorder of gastrointestinal tract in newborns. Enterokinase initiates digestion of protein by conversion of trypsinogen into trypsin. We analyzed the parents of unaffected deceased newborn with congenital enterokinase deficiency by exome sequencing. The results of exome sequencing identified a novel heterozygous frameshift deletion, c.151-155del p.Ala51Trpfs*5, in TMPRSS15 gene. Direct sequencing confirmed that the couple had heterozygous status. TMPRSS15 gene mutations are completely rare. To date, one small deletion and three nonsense mutations are reported in this gene in Human Gene Mutation Database (HGMD®). The identified mutation leads to complete absence of enzymatic activity.