TUBB2B and cerebellar ataxia: Exception is confined to a recessive disorder, Uner Tan syndrome, also known as cerebellar ataxia, impaired intellectual development, and disequilibrium syndrome (CAMRQ, MIM #224050), which has been linked to the homozygous pathogenic missense variant (p.Arg390Gln) in TUBB2B in one single family [59].