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Centre for Arab Genomic Studies a Division of Sheikh Hamdan Award for Medical Sciences Centre for Arab Genomic Studies A Division of Sheikh Hamdan Award for Medical Sciences The atalogue for ransmission enetics in rabs C T G A CTGA Database ATP-Binding Cassette, Subfamily A, Member 12 Alternative Names The ABCA12 gene is located on the long arm of ABCA12 chromosome 2, where it spans a length of 206 Kb. ATP-Binding Cassette Transporter 12 The gene consists of 53 exons, that together code ATP-Binding Cassette 12 for a 2595 amino acid protein with a molecular mass of 293 kDa. The fully functional protein Record Category contains two transmembrane domains, each with Gene locus about six membrane-spanning segments, and two ATP-binding domains or nucleotide-binding folds WHO-ICD (NBF), which are located in the cytoplasm. N.B.:Classification not applicable to gene loci. Epidemiology in the Arab World Incidence per 100,000 Live Births N/A to gene loci Saudi Arabia OMIM Number Wakil et al., (2016) described two unrelated Saudi 607800 patients with Autosomal Recessive Congenital Ichthyosis. Both patients were born to Mode of Inheritance consanguineous parents. The authors found one N/A novel mutation (p.Phe2300Leu) and one reported mutation (p.Ser1157Leu) in the ABCA12 gene in Gene Map Locus the two families. Combined approach of 2q35 homozygosity mapping and direct sequencing analysis was helpful in confirming the diagnosis of Description these patients. The ABCA12 gene encodes for the ATP-binding cassette sub-family A member 12 transporter References protein. Transporter proteins carry out the active Wakil SM, Binamer Y, Al-Dossari H, Al-Humaidy transportation of various molecules across extra- R, Thuraya RA, Khalifa O, Finsterer J, Meyer and intracellular membranes. The ABCA12 protein BF, Al Owain M. Novel mutations in TGM1 and plays a major role in lipid transport in cells that ABCA12 cause autosomal recessive congenital make up the epidermis. This lipid transport appears ichthyosis in five Saudi families. Int J Dermatol. to be important for normal development of the skin. 2016; 55(6):673-9. PMID: 27061915. Studies on animal models have suggested that the protein plays a critical role in the formation of the Related CTGA Records skin's permeability barrier via an effect on the Ichthyosis, Congenital, Autosomal Recessive 4A generation of a highly specialized class of ceramide esters. External Links https://ghr.nlm.nih.gov/gene/ABCA12 Mutations in ABCA12 have been associated with https://www.genecards.org/cgi- disruption of the lamellar permeability barrier and bin/carddisp.pl?gene=ABCA12 skin ichthyoses of variable severity. These include conditions like Ichthyosis, Congenital, Autosomal Contributors Recessive 4A and Harlequin Ichthyosis. Pratibha Nair: 14.11.2016 Ameera Balobaid: 1.11.2016 Molecular Genetics Copyright © Centre for Arab Genomic Studies 1 .
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