SUSD4 and Fryns syndrome: In Homo sapiens, the SUSD4 gene is located in the chromosome deletion linked with Fryns syndrome, which is an autosomal recessive multiple congenital neurodevelopmental disorder associated with intellectual disability (Shaffer et al., 2007) and SUSD4 variants have also been associated with autism spectrum disorders (Cuscó et al., 2009; Coe et al., 2019).