[Identification of gene mutation and prenatal diagnosis in a family with X-linked ichthyosis].
X-linked ichthyosis (XLI) is a metabolic disease with steroid sulfatase deficiency and often occurs at birth or shortly after birth. The encoding gene of steroid sulfatase, STS, is located on the short arm of the X chromosome, and STS deletion or mutation can lead to the development of this disease. This study collected the data on the clinical phenotype from a family, and the proband, a boy aged 11 years with full-term vaginal delivery, had dry and rough skin and black-brown scaly patches, mainly in the abdomen and extensor aspect of extremities. Peripheral blood samples were collected from each family member and DNA was extracted. Multiplex ligation-dependent probe amplification (MLPA) was used to measure the copy number of STS on the X chromosome. Whole-genome microarray was used to determine the size of the segment with microdeletion in the X chromosome. MLPA was then used for prenatal diagnosis for the mother of the proband. The results revealed that the proband and another two male patients had hemizygotes in STS deletion. Gene microarray identified a rare deletion with a size of 1.6 Mb at Xp22.31 (chrX: 6,516,735-8,131,442). Two female family members were found to be carriers. Prenatal diagnosis showed that the fetus carried by the proband's mother was a carrier of this microdeletion. This study showed STS gene deletion in this family of XLI, which causes the unique skin lesions of XLI. MLPA is a convenient and reliable technique for the molecular and prenatal diagnosis of XLI.
Department of Clinical Laboratory, Liuzhou Municipal Maternity and Child Healthcare Hospital, Liuzhou, Guangxi 545001, China. 439078813@qq.com.
Ji-Wei
JW
Huang
Ning
N
Tang
Wu-Gao
WG
Li
Zhe-Tao
ZT
Li
Shi-Qiang
SQ
Luo
Jing-Wen
JW
Li
Jun
J
Huang
Ti-Zhen
TZ
Yan
D002648:Child; D006801:Humans; D016114:Ichthyosis, X-Linked / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D009154:Mutation; D020641:Polymorphism, Single Nucleotide; D011296:Prenatal Diagnosis; D043266:Steryl-Sulfatase / Q000235:genetics
D043266:Steryl-Sulfatase