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HLA-B Haplotype B*27
RDB2015
Reverse hybridization kit for the determination
of the HLA-B allele B*27
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It has been known for a long
time that there is a close connection between the HLA-B*27 allele
and ankylosing spondylitis (SPA; synonym: Bechterew’s disease).
About 90-95% of all patients suffering from SPA are HLA-B*27 positive,
with a phaenotypic frequency of approx. 7-9% in Caucasians. Owing
to this high association with the disease, the typifying of HLA-B*27
is suitable for the differential diagnosis of Spondylitis ankylosans.
The other seronegative spondylarthritides are also associated to a
high percentage with HLA-B*27.
By the beginning of 1999, a total of fourteen different subtypes of
HLA-B*27 had been described (B*2701-B*2704, B*27051, B*27052, B*2706-B*2712
and B*2714). It is not known by which pathogenic mechanism HLA-B*27
causes a higher susceptibility to SPA. In isolated cases it has been
reported that the subtypes B*2703, B*2706 and B*2709 are less clearly
associated with SPA in some sections of the population, for example
B*2703 in West Africans and B*2706 in Thais. The dominant subtypes
in Caucasians are B*27051, with a frequency of approx. 90%, and B*2702,
approx. 5-10%; all other subtypes are extremely rare. This distribution
makes the subtypifying of HLA-B*27 seem unimportant at the present,
at least in differential diagnosis.
In addition to the traditional, serological methods of typifying HLA,
a series of DNA analysis methods have been described. Based on the
polymerase chain reaction, HLA-B*27 can be typified by amplification
with sequence-specific primers (SSP-PCR), by hybridization with sequence-specific
oligonucleotides (SSOP-PCR) or by the use of restriction length polymorphism.
The disadvantages of serological typification are that living cells
are needed for the test, and that there is a possibility of false
interpretation caused by cross-reactivity between the alloantisera
and monoclonal antibodies.
Typification by polymerase chain reaction has proved to be fundamentally
more exact and reliable. The individual samples are also easier to
store and transport, and can be tested repeatedly. In particular,
the typification of HLA-B*27 by hybridization with sequence-specific
oligonucleotides (SSOP-PCR) is a reliable, reproducible, robust and
easy to carry out method.
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References
Brewerton DA, Caffrey M, Hart FD ... (1973)
Ankylosing spondylitis and HL-A27
Lancet i: 904-907
Frankenberger B, Breitkopf S, Albert E ... (1996)
Routine Molecular Genotyping of HLA-B27 in Spondyloarthropathies Overcomes
the Obstacles of Serological Typing and Reveals an Increased B*2702
Frequency in Ankylosing Spondylitis
J. of Rheumatology 24: 899-903
Gonzales-Roces S, Alvarez MV, Gonzales S ... (1997)
HLA-B27 polymorphism and worldwide susceptibility to ankylosing spondylitis
Tissue Antigens 49: 116-123
Bozon MV, Delgado JC, Selvakumar A ... (1997)
Error rate for HLA-B antigen assignment by serology: implications
for proficiency testing and utilization of DNA-based typing methods
Tissue Antigens 50: 387-394
Elewaut D, Mielants H, Vandekerrckhove B ... (1997)
High frequency of 'missed' HLA-B loci by serologic determination in
patients with Spondyloarthropathy and chronic gut inflammation
Br. J. Rheumatol. 36: 185-189
Doxiadis IIN (1998)
Haupthistokompatibilitätsantigene (MHC-Antigene) und Krankheitsprädispositionen
In: Labor und Diagnose, 5.Auflage, S.878-888, TH-Books Verlagsgesellschaft
mbH, Frankfurt/Main |
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