Mutation detection in a case of Costello syndrome complicated by cutis laxa / 中华皮肤科杂志

Objective To report a case of Costello syndrome complicated by curis laxa,and to make a molecular genetic diagnosis.Methods Clinical data were collected from a case of Costello syndrome complicated by cutis laxa.Skin tissues were resected from the patient,and peripheral blood samples were obtained from the patient's parents and 150 unrelated healthy controls.Genomic DNA was extracted from these samples,and all the exons and their flanking sequences of the HRAS gene were analyzed by DNA sequencing.Results The 13-month-old female patient presented with growth retardation,severe malnutrition,coarse facial appearance,severely loose skin over the limbs,and decrease or disappearance of subcutaneous fat.A heterozygous mutation c.34G ＞ T (p.Gly12Cys) was detected in exon 2 of the HRAS gene in the patient,but not in her parents or 150 unrelated healthy controls.Conclusion The c.34G ＞ T (p.Gly12Cys) mutation in exon 2 of the HRAS gene may be responsible for Costello syndrome in the patient.

Mutation analysis of the LMNA gene in a child with Hutchinson-Gifford progeria syndrome / 中华皮肤科杂志

Objective To report a case of Hutchinson-Gilford progeria syndrome,and to make a molecular genetic diagnosis.Methods Peripheral blood samples were collected from a 12-month-old child with HutchinsonGilford progeria syndrome,his parents,and 150 unrelated healthy controls.DNA was extracted from these samples,and PCR was performed to amplify exon 11 of the LMNA gene and its flanking sequence followed by sequencing.Results The patient presented with scleroderma-like tight skin on the trunk,hair loss and prominent scalp veins for 9 months,whose body height and weight were two standard deviations below the mean.Physical examination showed thin skin and prominent superficial veins over the scalp.The skin over the trunk was tight,hard,shiny and dry with a small number of tiny scales,mottled pigmentation and hypopigmentation,induration and hypertrophy giving a cobblestone-like appearance.The subcutaneous fat was diminished on the lower limbs.Skeletal X-ray examination of the left hand revealed phalangeal acroosteolysis.A known heterozygous mutation c.1824C ＞ T (dbSNP:rs58596362) was detected in the exon 11 of the LMNA gene in the proband,but not in his parents or the 150 unrelated healthy controls.Conclusion The mutation c.1824C ＞T in the LMNA gene may be responsible for Hutchinson-Gilford progeria syndrome in this patient.