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Molecular characterization of the Fy(a-b-) phenotype in a Polish family
Ewa Karolak1, Magdalena Grodecka, Anna Suchanowska
1Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
Abstract:
The Fy(a-b-) phenotype, very rare in Caucasians and defined by the homozygous FY(*)B-33 allele, is associated with the -33T>C mutation in the promoter region of the FY gene. The allele FY(*)X is correlated with weak expression of Fy(b) antigen due to 265C>T and 298G>A mutations in FY(*)B allele. The purpose of this study was molecular characterization of Fy blood group antigens in Fy(a-b-) members of a Polish family. High-resolution melting analysis was performed to detect single nucleotide polymorphisms in amplified fragments of the FY gene. The Fy(a-b-) phenotype in three siblings of the Polish family was caused by the FY(*)X/FY(*)B-33 genotype.
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