Is methemoglobinemia a chromosomal disorder or a gene disorder?

Acquired and genetic: Your ethnicity wouldn't include Yakutsk people of Siberia? methemoglobin, like hemoglobin, acquires oxygen, but whereas hemoglobin will let go of it for use in our tissues, methemoglobin won't let go. Not a good situation. Some make methemoglobin when exposed to some chemicals like benzocaine, or nitrites. There are 2 inherited forms. http://www.nlm.nih.gov/medlineplus/ency/article/000562.htm