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.
We extend our warm thanks to the patient and relatives, for kindly donating both their time and biological samples to our genetic studies. We also thank the doctors who have provided us with the patient’s information. WYJ was supported by the Chinese National Natural Scientific Grants (No. 31171214 and U1132606).
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