“Structural” (coding)single nucleotide polymorphisms (within exon 1) | Codon 52 (Arg→Cys) | Allele C | Low (100 μg/l) |
Codon 54 (Gly→Asp) | Allele B | Low (100 μg/l) |
Codon 57 (Gly→Glu) | Allele D | Low (250 μg/l) |
| | | |
Promoter region single nucleotide substitutions | −550 g→c (alleles H/L) | HYA* | High (>3500 μg/l) |
−221 c→g (alleles X/Y) | LYA* | High (>2000 μg/l) |
+4 c→t (alleles P/Q) | LXA* | Intermediate (<1000 μg/l) |
| | | |
Compound heterozygotes (promoter polymorphisms linked to structural polymorphisms) | HY – 52Cys | HYAD | Intermediate (1000 μg/l) |
LY – 54Asp | LYB | Low (100 μg/l) |
LY – 57Glu | LYC | Low (200 μg/l) |