Abstract 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.
HUANG Ji-Wei,TANG Ning,LI Wu-Gao et al. Identification of gene mutation and prenatal diagnosis in a family with X-linked ichthyosis[J]. CJCP, 2016, 18(11): 1136-1140.
HUANG Ji-Wei,TANG Ning,LI Wu-Gao et al. Identification of gene mutation and prenatal diagnosis in a family with X-linked ichthyosis[J]. CJCP, 2016, 18(11): 1136-1140.
Webster D,France JT,Shapiro LJ,et al.X-linked ichthyosis due to steroid-sulphatase deficiency[J].Lancet,1978,1(8055):70-72.
[4]
Kearney HM,Thorland EC,Brown KK,et al.American College of Medical Genetics standards and guidelines for interpretation and reporting of postnatal constitutional copy number variants[J].Genet Med,2011,13(7):680-685.
Elias PM,Williams ML,Choi EH,et al.Role of cholesterol sulfate in epidermal structure and function:lessons from X-linked ichthyosis[J].Biochim Biophys Acta,2014,1841(3):353-361.
[8]
Akiyama M,Shimizu H.An update on molecular aspects of the non-syndromic ichthyoses[J].Exp Dermatol,2008,17(5):373-382.
[9]
Alperin ES,Shapiro LJ.Characterization of point mutations in patients with X-linked ichthyosis.Effects on the structure and function of the steroid sulfatase protein[J].J Biol Chem,1997,272(33):20756-20763.
[10]
Hand JL,Runke CK,Hodge JC.The phenotype spectrum of X-linked ichthyosis identified by chromosomal microarray[J].J Am Acad Dermatol,2015,72(4):617-627.
Ben Khelifa H,Soyah N,Ben-Abdallah-Bouhjar I,et al.Xp22.3 interstitial deletion:a recognizable chromosomal abnormality encompassing VCX3A and STS genes in a patient with X-linked ichthyosis and mental retardation[J].Gene,2013,527(2):578-583.
[13]
Brown CJ,Willard HF.Localization of a gene that escapes inactivation to the X chromosome proximal short arm:implications for X inactivation[J].Am J Hum Genet,1990,46(2):273-279.
[14]
Ellegren H.Characteristics,causes and evolutionary consequences of male-biased mutation[J].Proc Biol Sci,2007,274(1606):1-10.
