This test identifies the most common RHCE variant alleles.

In addition to RHD variant alleles, RHCE variant alleles are often seen in ethnically diverse populations; although they are more commonly found in individuals of African origin. Individuals with RHCE alleles will normally have variant expression of either or both Rhe and RhC antigens; different RHCE variant alleles with also encode RhCE proteins that lack various High Frequency Antigens (e.g. hr^S-, hr^B-, RH18-, RH34-).

Individuals with variable expression of the RhCE antigen have been shown to make alloantibodies with anti-e-like and/or anti-C-like specificity (e.g. anti-hr^S, anti-hr^B, anti-RH18 and anti-RH34), which are difficult to identify serologically. These clinically significant antibodies have been shown to cause transfusion reactions. Different combinations of RHCE variants can often be inherited with an RHD variant allele; these individuals may therefore make antibodies to RhCE antigens in addition to anti-D.  

Patients that would benefit from this test include:

• Haemoglobinopathy patients – to identify RHCE variants before transfusion
• Haemoglobinopathy patients – to identify RHCE variants in patients with anti-e-like or anti-C-like alloantibodies
• Obstetric patients of African origin – to identify RHCE variants in patients with anti-e-like or anti-C-like alloantibodies
• Other patients with variant expression of RhC or Rhe antigens.