Therefore, it is intriguing to note that the review [4] of over 200 15q11.2 BP1–BP2 microdeletion syndrome individuals, as meta-analysis, did not find either the NIPA1 associated cardinal disease: Spastic Paraplegia, the NIPA2 associated cardinal diseases: Angelman Syndrome and Prader–Willi Syndrome, the CYFIP1 associated cardinal disease: Fragile X Syndrome, or the TUBGCP5 associated cardinal disease: Prader–Willi Syndrome, except for the CYFIP1 associated cardinal disease: Autism, as presented in Table 15. The gene discussed is NIPA2; the disease is Spastic paraplegia.