HLA-B47 explained

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. The gene is located close to B47 between and locus.

B*4701 frequencies

HLA B*4701 frequencies

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

Notes and References

1. 2848993 . 2010 . Marsh . S. G. . Nomenclature for factors of the HLA system, 2010 . Tissue Antigens . 75 . 4 . 291–455 . Albert . E. D. . Bodmer . W. F. . Bontrop . R. E. . Dupont . B. . Erlich . H. A. . Fernández-Viña . M. . Geraghty . D. E. . Holdsworth . R. . Hurley . C. K. . Lau . M. . Lee . K. W. . Mach . B. . Maiers . M. . Mayr . W. R. . Müller . C. R. . Parham . P. . Petersdorf . E. W. . Sasazuki . T. . Strominger . J. L. . Svejgaard . A. . Terasaki . P. I. . Tiercy . J. M. . Trowsdale . J. . 20356336 . 10.1111/j.1399-0039.2010.01466.x .
2. Zemmour J, Ennis PD, Parham P, Dupont B . Comparison of the structure of HLA-B47 to HLA-B13 and its relationship to 21-hydroxylase deficiency . Immunogenetics . 27 . 4 . 281–7 . 1988 . 3257938 . 10.1007/BF00376123 .
3. http://www.ebi.ac.uk/imgt/hla/allele.html derived from IMGT/HLA
4. Middleton D, Menchaca L, Rood H, Komerofsky R . New allele frequency database . Tissue Antigens . 61 . 5 . 403–7 . 2003 . 12753660 . 10.1034/j.1399-0039.2003.00062.x . free .