[Exhaustive analysis of genetic mutations associated with protein S deficiency utilizing next-generation sequencing...

Protein S (PS) gene (PROS1) is found on chromosome 3 (3q11.1). To date, the reported detection rate of causative gene mutations in patients suspected of PS deficiency is only approximately 50%. To improve the detection rate of causative mutations, an exhaustive analysis of PROS1 was attempted using the next-generation sequencing method (NGS) to analyze the entire nucleotide sequence of PROS1 without analyzing those affected by pseudogenes. A total of 10 different mutations (three males and six females (52.9%) out of 17 patients (3 males and 14 females) with clinical PS deficiency were identified in this study. Remarkable improvements in the detection rate of causative mutations could not be obtained even with NGS analysis. These results suggested that the rate of diagnosis did not improve even after performing an exhaustive genetic analysis in patients clinically diagnosed with low PS antigen level and/or low PS activity. Although no reports were found on the gender gap in the rate of gene diagnosis for PS deficiency, the fluctuation of estrogen levels especially in women might cause a lower rate of diagnosis.