Open AccessDNA Methylation Status of SHOX-Flanking CpG Islands in Healthy Individuals and Short Stature Patients with Pseudoautosomal Copy Number Variations
Author(s) -
Kenichiro Ogushi,
Atsushi Hattori,
Erina Suzuki,
Hirohito Shima,
Masako Izawa,
Hideaki Yagasaki,
Reiko Horikawa,
Kimiaki Uetake,
Akihiro Umezawa,
Tomohiro Ishii,
Koji Muroya,
Noriyuki Namba,
Toshiaki Tanaka,
Yasuhiro Hirano,
Hitoshi Yamamoto,
Shun Soneda,
Kazuo Matsubara,
Masayo Kagami,
Mami Miyado,
Maki Fukami
Publication year - 2019
Publication title -
cytogenetic and genome research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.571
H-Index - 88
ISSN - 1424-8581
DOI - 10.1159/000500468
Subject(s) - pseudoautosomal region , haploinsufficiency , biology , dna methylation , cpg site , genetics , methylation , short stature , x chromosome , copy number variation , idiopathic short stature , gene , genome , gene expression , endocrinology , phenotype , growth hormone , hormone
SHOX resides in the short arm pseudoautosomal region (PAR1) of the sex chromosomes and escapes X inactivation. SHOX haploinsufficiency underlies idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). A substantial percentage of cases with SHOX haploinsufficiency arise from pseudoautosomal copy number variations (CNVs) involving putative enhancer regions of SHOX. Our previous study using peripheral blood samples showed that some CpG dinucleotides adjacent to SHOX exon 1 were hypomethylated in a healthy woman and methylated in a woman with gross X chromosomal rearrangements. However, it remains unknown whether submicroscopic pseudoautosomal CNVs cause aberrant DNA methylation of SHOX-flanking CpG islands. In this study, we examined the DNA methylation status of SHOX-flanking CpG islands in 50 healthy individuals and 10 ISS/LWD patients with pseudoautosomal CNVs. In silico analysis detected 3 CpG islands within the 20-kb region from the translation start site of SHOX. Pyrosequencing and bisulfite sequencing of genomic DNA samples revealed that these CpG islands were barely methylated in peripheral blood cells and cultured chondrocytes of healthy individuals, as well as in peripheral blood cells of ISS/LWD patients with pseudoautosomal CNVs. These results, in conjunction with our previous findings, indicate that the DNA methylation status of SHOX-flanking CpG islands can be affected by gross X-chromosomal abnormalities, but not by submicroscopic CNVs in PAR1. Such CNVs likely disturb SHOX expression through DNA methylation-independent mechanisms, which need to be determined in future studies.