Single nucleotide polymorphisms of the SEMA5A have been suspected in autism spectrum disorders and Parkinson's disease [51, 52]. SEMA5A is also included in the Cri-du-chat syndrome deleted region and the protein product semaphorin 5A is significantly elevated in rheumatoid arthritis [53, 54]. Here, SEMA5A is linked to Cri-du-chat syndrome.