Genetic diagnosis of one family with incomplete clinical data

Abstract

A 6-day-old female patient suddenly died of congestive heart failure, hepatomegaly and hypoglycemic encephalopathy. Tandem mass spectrometry (MS) analysis revealed a possibility of carnitine deficiency. However, many of the clinical symptoms had not yet occurred at that time, and the clinical data was incomplete. We aim to derive a systematic procedure of identifying pathogenic mutations for similar patients. Physicians could save patients' lives with effective treatment at a much earlier stage. Direct sequencing of the exons and exon-intron boundaries of GAA, SLC25A5, CPT1, CPT2, SLC25A20 and MUT genes were performed on the parents of the patient. DNA from the blood spots of the patient was analyzed for the MUT gene. The results revealed that the patient was a compound heterozygote with MUT. c. 729_730insTT and c. 1677-1G>A. cDNA sequence demonstrated MUT c. 1677-1G>A resulting in the deletion of eight nucleotides and the introduction of 13 novel amino acids before premature termination.