RHD genotype and zygosity analysis in the Chinese Southern Han D+, D− and D variant donors using the multiplex ligation‐dependent probe amplification assay

Abstract

The RH-MLPA assay correctly identified the common RHD variant alleles in the Chinese population. However, DNA sequencing was required to identify certain alleles; probes to detect these alleles should be added into the assay.

Functional analysis of novel RHD variants: splicing disruption is likely to be a common mechanism of variant D phenotype

“…We previously showed and confirm in this work that cellular splicing is affected by the c.1154G>C change, defining the RHD*weak D type 2 allele, and postulated that this mechanism is thought to be involved in the weakened expression of the D antigen associated with this allele . In this study, we show that a total skipping of exon 9 occurs with variation c.1154G>T, potentially resulting in the total absence of D antigen (i.e., D‐negative phenotype). While only partial skipping of exon 9 occurs with c.1154G>A, this variant has been reported in a D‐negative sample .…”

“…We demonstrated previously that the c.1154G>C variation is a SS variant . Since this work was published, two other substitutions at the same nucleotide position (i.e., c.1154G>A and c.1154G>T), which are both associated with a D‐negative phenotype, have been reported . In this study, we showed that although both variants result in the same phenotype, the mechanisms are slightly different.…”

“…4 Since this work was published, two other substitutions at the same nucleotide position (i.e., c.1154G>A and c.1154G>T), which are both associated with a D-negative phenotype, have been reported. 16,22 In this study, we showed that although both variants result in the same phenotype, the mechanisms are slightly different. Indeed, while c.1154G>T totally disrupts the inclusion of exon 9 within the mature transcript, which is compatible with the expression of a D-negative phenotype, c.1154G>A only partially alters splicing and a "normal" full length transcript, which is thought to be translated into a RhD(p.Gly385Asp) variant protein, remains.…”

“…An up‐to‐date review of the literature and the RhesusBase was performed . On the basis of their position relative to the constitutive SSs, 15 variations of the RHD gene, including eight exonic (i.e., first, antepenultimate and penultimate position of exons) and seven intronic variants were selected for functional analysis (Table ).…”

“…An up-to-date review of the literature and the RhesusBase was performed. 1,[13][14][15][16][17][18][19][20][21][22][23][24] On the basis of their position relative to the constitutive SSs, 15 variations of the RHD gene, including eight exonic (i.e., first, antepenultimate and penultimate position of exons) and seven intronic variants were selected for functional analysis (Table 1). In an effort to elucidate the potential effect of more internal synonymous variants on transcript expression, as reported for the c.960G>A variation by two independent studies, 4,13 the c.1056C>G and c.1065C>T variants, both located within exon 7 of the RHD gene, were also selected for functional study.…”