HLA-B47

major histocompatibility complex (human), class I, B47
Alleles	B*4701 B*4702 B*4703
Structure (See HLA-B)
Symbol(s)	HLA-B
EBI-HLA	B*4701
EBI-HLA	B*4702
EBI-HLA	B*4703
Locus	chr.6 6p21.31

HLA-B47 (B47) is an HLA–B serotype. The serotype identifies the HLA-B*47 gene products (B*4701, B*4702, B*4703) .^[1] Comparison of B47 nucleotide sequence with other HLA-B sequences shows a segment of 228 bp identical with B44 in the alpha 1 domain and a segment of 218 bp identical with B27 in the alpha 2 domain, but only a 91 bp segment of identity with B13 in the alpha 1 domain. The complex pattern of substitutions and their degree of divergence indicate that HLA-B13 and HLA-Bw47 alleles are not related by a simple mutational event.^[2] B47 is linked to (close to on the chromosome) a gene that causes adrenal deficiency. B47 is generally low in frequency and with highest known frequencies in Central and Western Africa. (For terminology help see: HLA-serotype tutorial)

Serotype

B47 serotype recognition of Some HLA B*47 allele-group gene products^[3]

B*47	B47	Other	Sample
allele	%	%	size (N)
4701	50	37	317
4702	40	40	5
4703	25	50	4

Serotyping for B47 is poor and typing is best performed with SSP-PCR or gene sequencing.

Disease Associations

B47 is linked to Adrenal 21-hydroxylase deficiency.^[2] The CYP21 gene is located close to B47 between HLA-B and HLA-DRB1 locus.

B*4701 frequencies

HLA B*4701 frequencies

		freq
ref.	Population	(%)
[4]	Bamileke (Cameroon)	2.6
[4]	Zapotec (Oaxaca, Mexico)	2.2
[4]	Niokholo Mandinka (Senegal)	1.6
[4]	Mbenzele Pygmy (CAR)	1.5
[4]	Nandi (Kenya)	1.3
[4]	Sudanese	1.3
[4]	Yaoundé City (Cameroon)	1.1
[4]	Lusaka (Zambia)	1.1
[4]	Central Portugal	1.0
[4]	Bulgaria	0.9
[4]	Czech Republic	0.9
[4]	Cape Verde Islands	0.8
[4]	Berber (Morocco)	0.7
[4]	Finland	0.6
[4]	Svans (Georgia)	0.6
[4]	Bergamo (Italy)	0.6
[4]	Romanians	0.6
[4]	North Delhi ((India))	0.5
[4]	Orkney Isles (Scotland)	0.5
[4]	Basque (Gipuzkoa, Spain)	0.5
[4]	Southeastern (France)	0.4
[4]	Oman	0.4
[4]	Kenya	0.3

References

1. Marsh SG, Albert ED, Bodmer WF, et al. (2005). "Nomenclature for factors of the HLA system, 2004". Tissue Antigens. 65 (4): 301–69. doi:10.1111/j.1399-0039.2005.00379.x. PMID 15787720.
2. Zemmour J, Ennis PD, Parham P, Dupont B (1988). "Comparison of the structure of HLA-B47 to HLA-B13 and its relationship to 21-hydroxylase deficiency". Immunogenetics. 27 (4): 281–7. doi:10.1007/BF00376123. PMID 3257938.
3. derived from IMGT/HLA
4. Middleton D, Menchaca L, Rood H, Komerofsky R (2003). "New allele frequency database: http://www.allelefrequencies.net". Tissue Antigens. 61 (5): 403–7. doi:10.1034/j.1399-0039.2003.00062.x. PMID 12753660. External link in |title= (help)