How are the CYP1A2 alleles inherited?

CYP1A2 is located on an autosome (chromosome 15). Autosomes are inherited in pairs - one from each parent. Individuals can inherit two copies of the same allele (either homozygous "fast" or homozygous "slow") or one copy of each allele (heterozygous). People with at least one copy of the "slow" allele are slow caffeine metabolizers.