B4GALNT1 encodes β-1,4-N-acetyl-galactosaminyl transferase 1 (GM2 synthase), an enzyme involved in the biosynthesis of complex gangliosides. Mutations in the B4GALNT1 gene cause hereditary spastic paraplegia 26 (SPG26), an autosomal recessive disorder characterized by onset of gait abnormalities due to lower limb spasticity and muscle weakness. A homozygous missense mutation, c.1514G>A (p.Arg505His), in B4GALNT1 was identified in Old Order Amish as the genetic cause of this condition. This test will specifically analyze the c.1514G>A mutation in the Amish population.
1 - 2 weeks