Rapidly screening variants of uncertain significance in the MAP3K1 gene for phenotypic effects

DNA sequencing of candidate genes or whole exomes on a diagnostic or investigational basis will yield a plethora of variants of uncertain significance whose potential phenotypic roles cannot be readily demonstrated by prediction programs, SNP databases nor conventional genetic analysis. Many variants may produce phenotypic changes in the encoded proteins by affecting the quantity, post-translational modification or protein interactions. Here, we establish the application of the method of flow cytometry following immunoprecipitation to show that known protein interactions are altered in the B-lymphoblastoid cells of patients with 46,XY gonadal dysgenesis arising from mutations in the MAP3K1 gene. This method can be scaled readily to test multiple interactions for many variants simultaneously from available tissues as well as quantify the effects of variants on protein accumulation and post-translational modification, thus providing an efficient means for screening variants of uncertain significance for phenotypic effects.