ABSTRACT
OBJECTIVE@#To explore the clinical features and genetic basis of a patient with glycogen storage disease type VI (GSD-VI).@*METHODS@#Clinical data of the patient was collected. Genomic DNA was extracted from peripheral blood samples of the proband and his parents. Genetic variants were detected by using whole exome sequencing. Candidate variants were verified by Sanger sequencing followed by bioinformatics analysis.@*RESULTS@#The proband presented fasting hypoglycemia, hepatomegaly, growth retardation, transaminitis, metabolic acidosis and hyperlactatemia. Liver biopsy indicated GSD. Novel compound heterozygous PYGL gene variants (c.2089A>G/c.158_160delACT) were detected in the proband. Compound heterozygosity was confirmed by Sanger sequencing of the patient's genomic DNA. Provean and MutationTaster predicted the two variants as deleterious and the variant sites are highly conserved.@*CONCLUSION@#The compound heterozygous variants (c.2089A>G/c.158_160delACT) of PYGL gene probably underlay the GSD in the patient. The two novel variants have expanded the spectrum of PYGL gene variants and provided the basis for genetic counseling of the family.
Subject(s)
Child , Humans , Family , Genetic Testing , Glycogen Storage Disease Type VI/genetics , Mutation , Exome SequencingABSTRACT
Objectives To investigate the clinical features of progressive familial intrahepatic cholestasis type 2 (PFIC2) and to illustrate the importance of genetic diagnosis. Methods The mutations in 27 exons of ABCB11 encoding bile salt export pump (BSEP) were identiifed using polymerase chain reaction (PCR) and direct DNA sequencing in 6 children with suspected PFIC2. The pathogenicity of the newly identiifed mutations were predicted by SIFT, PolyPhen-2, SNPs&GO software. The clini-cal features and laboratory examinations were reviewed. Results Four disease-causing mutations, p.R928*, p.E554K, p.R575Q and p.Y337H were identiifed, and the last three mutations were novel. These three kinds of novel mutations can cause the disease. Two children with genetic diagnosis had such manifestations as onset within a month after birth, jaundice, hepatosplenomegaly, upset, increased levels of total bilirubin and direct bilirubin, GGT<100 U/L and high levels of total bile acid. Conclusions Genetic diagnosis is a potent tool for clinical diagnosis of PFIC2.