Identification of a new HLA-DRB1 allele (DRB1*0318) in three members of a Caucasian Spanish family.
This communication reports the identification of a new allele HLA-DRB1*03 in three members of a Caucasian Spanish family. The new allele has been officially named HLA-DRB1*0318 by the World Health Organization Nomenclature Committee. The exon 2 sequence of this new allele is identical to that of DRB1*03011 except for the first nucleotide of codon 45. The nucleotide change (C replacing G) leads to the amino acid substitution of glycine to arginine (GGG-->CGG) at position 45. This position of the beta1 domain shows very little polymorphism among DRB1* alleles (nucleotide changes at this position have only been reported for DRB1*1436 and DRB1*0105) and locates in the vicinity of the highly polymorphic position 47, which is a constituent of the groove's pocket interacting with the amino acid position 7 of the antigen peptide. The familial study showed that the new allele was maternally transmitted into the HLA-A*3002, -B*1801, -Cw*0501, -DRB1*0318, -DRB3*0202, -DQB1*0201 haplotype. Interestingly, the two siblings of the family, which were HLA identical and suffered of insulin-dependent diabetes mellitus (IDDM), were carriers of the two HLA haplotypes (DRB1*03/DQB1*0201 and DRB1*04/DQB1*0302) reported as susceptibility markers to IDDM in Caucasians.
Ercilla
M G
MG
Institut Clínic d'Infeccions i Immunologia (ICII), Institut d'Investigacions August Pi i Sunyer (IDIBAPS), Hospital Clínic, Barcelona, Spain. gercilla@clinic.ub.es
Guardia
A
A
Suárez
B
B
Arias
M T
MT
Fabregat
V
V
Costa
M
M
Salinas
I
I
Martorell
J
J
Vives
J
J
Lozano
F
F
D000483:Alleles; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D006801:Humans; D008969:Molecular Sequence Data; D013030:Spain / Q000208:ethnology; D044465:White People / Q000235:genetics*
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553504:HLA-DRB1*03:18 antigen