The following mutations have been found: c.983T>C (p.Leu328Pro), c.799_1034-429delinsTTATGA (p.Gln267fs), c.1360C-T (R454X), c.637_638insAAAC (Gln214ThrfsTer31), c.499C>T (R167*), c.1537delT (S513Lfs*7), c.1566+1G>T (p.?). Pathophysiological mechanism is unknown.
New patients can be found using exome/genome sequencing. Genetic testing of known variants can be done using Sanger sequencing.