immunolinvest45_406.pdf 1.2 MB
藤原 純子 島根大学医学部法医学講座
植木 美鈴 福井大学医学部病態遺伝生化学領域
木村 かおり 島根大学医学部法医学講座
飯田 礼子 福井大学医学部・生命基礎科学領域
竹下 治男 島根大学医学部法医学講座
安田 年博 福井大学医学部病態遺伝生化学領域
OBJECTIVE: To continue our previous investigations, we have extensively investigated the function of the 61, 41, and 35 non-synonymous single nucleotide polymorphisms (SNPs) in the human genes encoding DNASE1, DNASE1L3, and DNASE2, respectively, potentially relevant to autoimmune diseases.
METHODS: The site-directed mutagenesis was employed to amino acid-substituted constructs corresponding to each SNP. The COS-7 cells were transfected with each vector and DNase activity was assayed by the single radial enzyme diffusion method. By using PolyPhen-2, changes in the DNase function of each non-synonymous SNP were predicted. Genotyping of all the non-synonymous SNPs was performed in 14 different populations including 3 ethnic groups using the polymerase chain reaction followed by the restriction fragment length polymorphism method.
RESULTS: Expression analysis demonstrated these SNPs to be classified into four categories with regard to the effect on DNase activity: SNPs not affecting the activity level, ones reducing it, ones abolishing it, and ones elevating it. In particular, 9, 5, and 4 SNPs producing a loss-of-function variant of the enzymes in DNASE1, DNASE1L3, and DNASE2, respectively, were confirmed. SNPs producing DNase loss of function can be estimated by PolyPhen-2 to be "probably damaging" with a high accuracy of prediction. Almost all of these functional SNPs producing a loss of function or substantially low activity-harboring forms exhibited a mono-allelic distribution in all of the populations.
CONCLUSION: A minor allele of functional SNPs, despite the remarkably low genetic heterogeneity of the SNPs, might be a genetic risk factor for autoimmune diseases.
deoxyribonuclease (DNase) family
Taylor & Francis
This is an Accepted Manuscript of an article published by Taylor & Francis in Immunological investigations on 2016, available online: http://www.tandfonline.com/10.3109/08820139.2016.1157813.