SEQUENCE CHARACTERIZATION OF A NEWLY IDENTIFIED HUMAN ALPHA-TUBULIN GENE (TUBA2)

We report on the isolation and initial characterization of a human alp ha-tubulin gene named TUBA2. This gene is located in the 13q11 region and has been considered a candidate gene for two nonsyndromic neafness es, DFNB1 and DFNA3. The gene, with a minimum size of 6.5 kb, contains five exons and four introns starting at codon positions 1, 76, 125, a nd 352, one of which is inserted between the initiation methionine cod on and the codon specifying the second amino acid, arginine 2. Neither rearrangement nor point mutation was found in the coding region of th e gene in DFNB1- and DFNA3-affected patients. The gene was therefore u nlikely to be responsible for either of these deafnesses. During the c haracterization of TUBA2, the gene encoding connexin 26 was proven to be responsible for both DFNB1 and DFNA3 (D. P. Kelsell et al., 1997, N ature 387: 80-83). However, the present data offer the possibility of testing the involvement of the TUBA2 gene in the Clouston hidrotic ect odermal dysplasia and the Kabuki syndrome, two genetic diseases that h ave recently been mapped to the 13q11 region. (C) 1998 Academic Press.