title: Microphthalmia-associated transcription factor mutations are associated with white-spotted coat color in swamp buffalo.
abstract: A candidate gene analysis of the microphthalmia-associated transcription factor (MITF) gene was used in an attempt to identify the genetic basis for a white-spotted coat color phenotype in the Asian swamp buffalo (Bubalus bubalis carabanensis). Ninety-three buffaloes-32 solid, 38 spotted and 23 white individuals-were Sanger-sequenced for all MITF exons as well as highly conserved intronic and flanking regions. MITF cDNA representing skin and iris tissue from six spotted, nine solid and one white buffaloes was also Sanger-sequenced to confirm detected mutations. Two independent loss-of-function mutations, a premature stop codon (c.328C>T, p.Arg110*) and a donor splice-site mutation (c.840+2T>A, p.Glu281_Leu282Ins8), both of which cause white-spotted coat color in swamp buffaloes, were identified. The nonsense mutation leads to a premature stop codon in exon 3, and likely removal of the resulting mRNA via nonsense-mediated decay pathway, whereas the donor splice-site mutation leads to aberrant splicing of exon 8 that encodes part of a highly conserved region of MITF. The resulting insertion of eight amino acid residues is expected to perturb the leucine zipper part in the basic helix-loop-helix leucine zipper (bHLH-Zip) domain and will most likely influence dimerization and DNA binding capacity. Electrophoretic mobility shift assay was performed using mutant and wild-type MITF proteins and showed that the mutant MITF protein resulting from the splice-site mutation decreased in vitro DNA binding capacity compared to wild-type MITF. White-spotted buffalo bulls are sacrificed in funeral ceremonies in Tana Toraja, Indonesia, because they are considered holy, and our results show that genetic variation causes a tie to the cultural use of these buffaloes.
authors.affiliation: Graduate School, Bogor Agricultural University (IPB), 16680, Bogor, Indonesia.|Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.|Research Center for Biotechnology, Indonesian Institute for Sciences (LIPI), 16912, Cibinong, Indonesia.
authors.forename: Y
authors.initials: Y
authors.lastname: Yusnizar
authors.affiliation: Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.|Department of Immunology, Genetics and Pathology, Uppsala University, SE-751 08, Uppsala, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Wilbe
authors.affiliation: Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.
authors.forename: A O
authors.initials: AO
authors.lastname: Herlino
authors.affiliation: Department of Animal Productions and Technology, Faculty of Animal Sciences, Bogor Agricultural University (IPB), 16680, Bogor, Indonesia.
authors.forename: C
authors.initials: C
authors.lastname: Sumantri
authors.affiliation: Department of Animal Productions and Technology, Faculty of Animal Sciences, Bogor Agricultural University (IPB), 16680, Bogor, Indonesia.
authors.forename: R Rachman
authors.initials: RR
authors.lastname: Noor
authors.affiliation: Department of Anatomy, Physiology and Pharmacology, Faculty of Veterinary Medicine, Bogor Agricultural University (IPB), 16680, Bogor, Indonesia.
authors.forename: A
authors.initials: A
authors.lastname: Boediono
authors.affiliation: Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.|Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Andersson
authors.affiliation: Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences (SLU), SE-750 07, Uppsala, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Andersson
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D002020:Buffaloes / Q000235:genetics*; D004252:DNA Mutational Analysis; D006197:Hair; D051739:Microphthalmia-Associated Transcription Factor / Q000235:genetics*; D050505:Mutant Proteins / Q000235:genetics; D010641:Phenotype; D010858:Pigmentation / Q000235:genetics*
chemical_list: D051739:Microphthalmia-Associated Transcription Factor; D050505:Mutant Proteins
keywords: Bubalus bubalis; MITF; donor splice-site mutation; nonsense mutation