RESUMO
Myotonic dystrophy type 1 (DM1, OMIM 160900) is a rare autosomal dominant hereditary disease. A case of DM1 patient with early onset diabetes and decreased muscle strength was treated in the Department of Endocrinology, Third Xiangya Hospital, Central South University. The peripheral blood of the patient was collected to extract DNA for gene detection. It was found that the triple nucleotide CTG repeat in the 3'-untranslated region (3'-UTR) of the dystrophia myotonica protein kinase (DMPK) gene was more than 100 times, and the diagnosis of DM1 was clear. For diabetes patients with multiple system abnormalities such as muscle symptoms, attention should be paid to the screening of DM1, a rare disease.
Assuntos
Humanos , Distrofia Miotônica/genética , Anormalidades Múltiplas , Hospitais , Universidades , Diabetes MellitusRESUMO
Alstrom syndrome is a rare autosomal recessive multi-organ syndrome caused by variations in ALMS1 gene. We explore the underlying genetic cause in one case of Alstrom syndrome who manifasted childhood obesity, hyperinsulinemia, and acanthosis using the whole-exome sequencing, to improve clinicians′ awareness of the disease. The proband presented with obesity, acanthosis, hyperinsulinemia, and fatty liver in childhood, but without typical manifestations of Alstrom syndrome, such as retinal degeneration, hearing impairment and cardiomyopathty. Whole-exome sequencing revealed that the proband carried a complex heterozygous ALMS1 mutation, including c. 1A>T(p.M1? ) and c. 8971G>C, p. D2991H. Family verification found that his father wass heterozygous for the c. 1A>T mutation, his mother was heterozygous for the c. 8971G>C mutation, and the sister′s ALMS1 gene detection and clinical phenotype were normal, which was consistent with the autosomal recessive inheritance pattern. Through bioinformatics analysis, the new mutations c. 1A>T and c. 8971G>C in the ALMS1 gene were identified as deleterious mutations. In this study, a single case of Alstrom syndrome was reported with childhood obesity, acanthosis nigricans, and hyperinsulinemia as the main manifestations, and two new ALMSl gene mutations were discovered, which expanded the phenotype and pathogenic mutation spectrum of Alstrom syndrome.