%0 Journal Article %T Association of a rare NOTCH4 coding variant with systemic sclerosis: a family-based whole exome sequencing study. %A Cardinale CJ %A Li D %A Tian L %A Connolly JJ %A March ME %A Hou C %A Wang F %A Snyder J %A Kim CE %A Chiavacci RM %A Sleiman PM %A Burnham JM %A Hakonarson H %J BMC Musculoskelet Disord %V 17 %N 1 %D 11 2016 9 %M 27829420 %F 2.562 %R 10.1186/s12891-016-1320-4 %X Systemic sclerosis (SSc) is a rheumatologic disease with a multifactorial etiology. Genome-wide association studies imply a polygenic, complex mode of inheritance with contributions from variation at the human leukocyte antigen locus and non-coding variation at a locus on chromosome 6p21, among other modestly impactful loci. Here we describe an 8-year-old female proband presenting with diffuse cutaneous SSc/scleroderma and a family history of SSc in a grandfather and maternal aunt.
We employed whole exome sequencing (WES) of three members of this family. We examined rare missense, nonsense, splice-altering, and coding indels matching an autosomal dominant inheritance model. We selected one missense variant for Sanger sequencing confirmation based on its predicted impact on gene function and location in a known SSc genetic locus.
Bioinformatic analysis found eight candidate variants meeting our criteria. We identified a very rare missense variant in the regulatory NODP domain of NOTCH4 located at the 6p21 locus, c.4245G > A:p.Met1415Ile, segregating with the phenotype. This allele has a frequency of 1.83 × 10-5 by the data of the Exome Aggregation Consortium.
This family suggests a novel mechanism of SSc pathogenesis in which a rare and penetrant coding variation can substantially elevate disease risk in contrast to the more modest non-coding variation typically found at this locus. These results suggest that modulation of the NOTCH4 gene might be responsible for the association signal at chromosome 6p21 in SSc.