Hemizygous deletion in the OTC gene results in ornithine transcarbamylase deficiency: A case report

BACKGROUND Ornithine transcarbamylase deficiency(OTCD) is a common ornithine cycle disorder, and OTC gene variation is the main pathogenic factor of this disease. This study explored and validated a variant in the OTC gene.CASE SUMMARY The neonate exhibited high blood ammonia, lactic acid, and homocysteine levels on the fifth day after birth. A novel deletion variant in the OTC gene [NM＿000531.5, c.970＿979 del TTCCCAGAGG, p.Phe324 Glnfs Ter16] was uncovered by exome sequencing. The variant caused a protein-coding frameshift and resulted in early translation termination at the 16 th amino acid after the variant site.CONCLUSION Our results provide a novel pathogenic variant in OTC and related clinical features for further OTCD screening and clinical consultation.