Intron 3 length polymorphism of the Rhesus genes. The 3′ region of intron 3 was amplified by PCR using primers RB46 and RB5. (A) The agarose gel shows a 1,722-bp product for theRHCE gene. The 1,420-bp product is representative of theRHD gene. In the D^VI type II sample, aRHD-specific product is found. D^VI type Iand D^VI type III samples show noRHD-specific product. (B) The nucleotide sequence of the 3′ part of intron 3 of the RHCE gene starting 1,556 nucleotides 5′ from exon 4 and of the corresponding parts of theRHD gene comprising the diagnostic 288 bp deletion are shown. Dashes denote nucleotides in the RHD gene that are identical, dots denote deletions. Nucleic acid sequence accession numbers were Z97030(RHCE; 1,580 bp) and Z97031 (RHD; 1,278 bp).