Recessive genomic and phenotypic variation in consanguineous families with cerebral palsy

Cerebral palsy (CP) is a neurodevelopmental disorder of motor function, with genetic etiologies, particularly <i>de novo</i> variants, identified in approximately one-third of cases. The contribution of consanguinity - long-recognized as a CP risk factor - has remained undefined. Here, we report findings from 188 primarily consanguineous Middle Eastern families with CP and identified putative causative genes in nearly three-quarters. The majority demonstrated recessive inheritance, although multi-level consanguinity and multilocus pathogenic variants complicated Mendelian assortment analyses. We identified 110 known CP-associated genes - five with phenotypic expansions and three others exhibiting new recessive inheritance patterns - and 24 novel candidates. We characterized ten candidates as high-confidence based on independent replication and protein modeling. We experimentally validated a role for <i>SUCO</i> variants in CP and newly identified a role for mid-gestational migrating excitatory neurons in the disorder. These findings highlight new genes, pathways, and phenotypes that reveal striking genomic diversity in CP.