Identification of a Novel Missense Mutation in the LMX1B Gene Associated with Nail-Patella Syndrome in a Chinese Family

Aim Nail-patella syndrome is an autosomal dominant disorder caused by mutations in LMX1B gene, affecting different systems including skeleton-muscular, renal and ocular system. The complicated relationship between genotype and phenotype is still unclear. Here, we report a novel missense mutation in a Chinese family. Method Clinical information of the family was collected, along with the peripheral blood sample. To investigate the pathogenic mutation, whole exome sequencing was conducted. Subsequently, Sanger sequencing was utilized to confirm the suspicious mutation. Bioinformatic tools was used to predict the 3D structure modification and pathogenicity caused by the mutation. Results The proband in our study showed manifestations including nail malformation, patella dysplasia, restricted elbow movement and pes planus Both his mother and sister also displayed skeletal system symptoms. We identified a novel mutation c.812G > C (p.R271T) in this family, which encodes an amino acid within the homeodomain, disturbing its ability to bind DNA, leading to the onset of the syndrome. Conclusion Nail-patella syndrome is a rare disorder affecting multiple systems. Manifestations in this family mainly focus on the skeletal system with variations among different members. Our study reports a novel mutation of this disease, previously unreported in literature.