Infantile Systemic Hyalinosis: Novel Founder Mutation in the Initiation Codon among “Malis (Farmers)” in Jodhpur

Infantile systemic hyalinosis (OMIM 236490) is a progressive autosomal recessive disorder characterized by widespread deposition of hyaline material in many tissues leading to multiple subcutaneous skin nodules, gingival hypertrophy and joint contractures. The authors describe five children from four unrelated families, from the “mali (farmer)” community in Jodhpur, with the disorder. All of them had classical clinical features, and four died from severe infections between age of 7 mo to 3 y. Two affected children had the same, but novel mutation in the initiation codon, in homozygous form c.1 A > G; p. M1? in capillary morphogenesis protein-2 (CMG2), or ANTXR2 gene on chromosome 4q21.21. The other two parents had the same mutation in heterozygous form. It is likely that this is a founder mutation in this community.