KINSSHIP Syndrome without Mesomelia: A Case Report and Review of Literature

KINSSHIP syndrome is a recently characterized disorder caused by pathogenic variants in the AFF3 gene, with around 22 reported worldwide. The syndrome presents with a highly recognizable phenotype, including horseshoe kidney, Nievergelt/Savarirayan-type mesomelic dysplasia, seizures, hypertrichosis, intellectual disability, and pulmonary involvement. We report the first case of KINSSHIP syndrome from India, identified in a girl with syndromic intellectual disability. Genetic analysis revealed the recurrent pathogenic variant p.Ala258Thr in the AFF3 gene. AFF3 -related KINSSHIP syndrome is marked by intellectual disability, a characteristic facial gestalt, and renal anomalies. Approximately half of the reported cases carry the recurrent p.Ala258Thr variant. While skeletal abnormalities such as mesomelia are commonly described, they may not be present in all affected individuals.