THE REGULATORY LANDSCAPE OF THE RET GENE IN HIRSCHSPRUNG DISEASE

Hirschsprung Disease;HSCR;RET;not listed

Karasaki, Kameko MakanalaniZhao, Haiqing ;

Johns Hopkins University

关键词: Hirschsprung Disease;    HSCR;    RET;    not listed;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/40686/KARASAKI-THESIS-2016.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

Hirschsprung disease (HSCR), or congenital aganglionosis, is characterized by a contiguous lack of enteric neurons in variable segments of the gut. Both coding and non-coding mutations in the receptor tyrosine kinase RET are the major genetic drivers of the disease, although all disease causing mutations in RET have not yet been identified. A prior Genome Wide Association Study (GWAS) using 220 HSCR trios identified 38 common single nucleotide polymorphisms (SNPs) that are significantly associated with the disease and are located in non-coding regions at the RET locus. Eight of these SNPs disrupt known RET transcription factor binding sites in the human neuroblastoma cell line, SK-N-SH, and are located within enhancer elements. Three of these eight SNPs show differential enhancer activity between the non-risk and disease associated (risk) alleles, or an allelic difference. I sought to determine how many of the remaining 30 SNPs displayed enhancer activity and allelic differences by using a dual in vitro luciferase reporter assay in SK-N-SH cells. My studies revealed that 28 SNPs had enhancer activity while seven of those displayed allelic differences. The SNPs that showed an allelic difference and affected enhancer activity potentially disrupt binding sites for PAX3, MZF1, ZNF263, and Myb/Mybl1.Therefore, the genetic risk of HSCR susceptibility at RET is conferred by allelic differences at at least 10 enhancer elements, demonstrating the high degree of intra-locus risk heterogeneity.