CYB5A Chromosome 18
Cytochrome b5 type A
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What This Gene Does
The protein encoded by this gene is a membrane-bound cytochrome that reduces ferric hemoglobin (methemoglobin) to ferrous hemoglobin, which is required for stearyl-CoA-desaturase activity. Defects in this gene are a cause of type IV hereditary methemoglobinemia. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jun 2010]
Associated Conditions (1)
Methemoglobinemia type 4
Key Variants
RS75160992
Conflicting classifications of pathogenicity
Health Risk
RS1555688659
Likely pathogenic
Methemoglobinemia type 4, Methemoglobinemia type 4
Health Risk
RS1555691399
Likely pathogenic
Methemoglobinemia type 4, Methemoglobinemia type 4
Health Risk
RS794728010
Pathogenic
Methemoglobinemia type 4, Methemoglobinemia type 4
Health Risk
All Variants (4)
| RSID | Category | Clinical Significance | Conditions |
|---|---|---|---|
| RS75160992 | Health Risk | Conflicting classifications of pathogenicity | — |
| RS1555688659 | Health Risk | Likely pathogenic | Methemoglobinemia type 4, Methemoglobinemia type 4 |
| RS1555691399 | Health Risk | Likely pathogenic | Methemoglobinemia type 4, Methemoglobinemia type 4 |
| RS794728010 | Health Risk | Pathogenic | Methemoglobinemia type 4, Methemoglobinemia type 4 |