In family 9, a single affected individual was found to have a homozygous missense variant (c.2065G > T; p.Asp689Tyr) in the DDHD2 gene (NM_015214.3), which is responsible for Spastic paraplegia 54, autosomal recessive (OMIM 615033). Here, DDHD2 is linked to Spastic paraplegia.