Edition of 18 September 2024

A new study published in Journal of Medical Genetics presented rare bi-allelic variants in PLXNB2, which encodes a transmembrane receptor participating in axonal guidance and cell migration, among 8 individuals from 6 families afflicted by two main features: amelogenesis imperfecta (AI) and sensorineural hearing loss (SNHL), along with other clinical conditions such as intellectual disability, ocular disease, ear developmental abnormalities and lymphoedema. Various analysis identified PLXNB2 deficiency as a cause of a new autosomal recessive, phenotypically diverse syndrome with AI and SNHL as core features.

A new study published in Journal of Medical Genetics determined a heterozygous de novo variant in TUBA4A, which encodes α-tubulin, a subunit of the microtubule cytoskeleton involved in many cellular functions, among 2 unrelated individuals with diagnosed sporadic congenital myopathy with focal myofibrillar disorganization and rimmed vacuoles. Various analysis demonstrated that TUBA4A is a new genetic cause of congenital myopathy with myopathological changes, expanding the genetic/phenotypic spectrum of congenital myopathies and tubulinopathies.