[Molecular basis of partial D phenotypes in Chinese]

Area of Science:

• Genetics
• Immunology
• Molecular Biology

Background:

• Partial D phenotypes, characterized by weak D antigen expression, can lead to transfusion complications.
• Understanding the molecular basis of these variants is crucial for accurate blood typing and transfusion practices.
• Previous studies on partial D phenotypes in the Chinese population are limited.

Purpose of the Study:

• To investigate the molecular basis of partial D phenotypes in the Chinese population.
• To screen for and characterize D variants with weak D expression.
• To identify novel or previously unreported partial D phenotypes.

Main Methods:

• Screening of 22 cases with weak D phenotype using the indirect anti-human globulin test (IAT).
• Employing polymerase chain reaction-sequence specific primer (PCR-SSP) to amplify RHD specific exons and flanking regions.
• Direct sequencing of amplification products to determine the molecular basis of D variants.

Main Results:

• Ten cases of partial D phenotypes were detected, including D Va (Kou.), D Va (Hus.), D Va-like (YH.), and D VI type III.
• Seven cases were identified as D VI type III.
• All ten partial D phenotypes exhibited one RHD allele deletion.

Conclusions:

• The molecular basis of ten partial D phenotypes was confirmed in the Chinese population.
• D Va (Kou.) and D Va-like (YH.) phenotypes are reported for the first time in this population.
• RHD allele deletion is a common molecular mechanism underlying these partial D phenotypes.