However, the gene known to be responsible for NPS, LMX1B, only appears to be deleted in patient 4, while the minimal deletion interval in patient 1 starts 302 base pairs downstream from LMX1B. However, as the deletion breakpoints have not been sequenced, it is possible that the deletion in patient 1 in fact could extend into the coding region of LMX1B, causing features of NPS. Here, LMX1B is linked to nail-patella syndrome.