Susceptibility to insulin-dependent diabetes mellitus and short cytoplasmic ATP-binding domain TAP2*01 alleles.
TAP2 genes are placed within the HLA complex, have limited genetic variability and encode two main groups of peptide transporter proteins, the so-called TAP2*01 alleles, with a short ATP-binding domain, and the TAP2*0201 allele with a long domain. These transporters carry antigenic peptides from cytoplasm across the endoplasmic reticulum membrane to release them into nascent HLA class I molecules, which will then travel towards the plasma membrane. The shorter TAP2*01 alleles are present in 99% of diabetics and 90% of controls; these alleles may add slight, although significant and independent, susceptibility to diabetes, particularly in subjects carrying non-Asp 57 at beta DQ. Moreover, this increased susceptibility is not due to linkage disequilibrium with other HLA markers (i.e.: DR4), which does not exist in our Spanish population.
Department of Immunology and Pediatric Endocrinology, Hospital 12 de Octubre, Universidad Complutense, Madrid, Spain.
J
J
Martinez-Laso
J M
JM
Martin-Villa
M
M
Alvarez
N
N
Martinez-Quiles
G
G
Lledo
A
A
Arnaiz-Villena
D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics*; D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes
D000071450:ATP Binding Cassette Transporter, Subfamily B, Member 3; D018528:ATP-Binding Cassette Transporters; D015345:Oligonucleotide Probes; C071692:TAP2 protein, human