For many people, part of their morning routine always includes a hot cup of
coffee in order to start another day of their busy lives. Some compounds in coffee, such as
caffeic acid and chlorogenic acid, have antioxidant properties that may help protect
against heart disease (Sohemy et al., 2007).
Caffeine is one of the many reasons as to
why coffee is consumed, and it has shown to increase the risk of myocardial infarctions in
those individuals with certain mutations in their CYP1A2 gene (Sohemy et al., 2007). The
CYP1A2 gene can also lead to cancer as it works with other proteins to biologically
activate carcinogenic polycyclic aromatic hydrocarbons (PAHs) (Zhou et al., 2009).
The CYP1A2 gene codes for a protein, which is a member of the cytochrome P450
superfamily of enzymes (Ou-Yang et al, 2000). The cytochrome P450 proteins are
monooxygenases; these enzymes catalyze reactions involved in drug metabolism and
synthesis of cholesterol, steroids and lipids (Kot & Daniel, 2009).
CYP1A2 activity can
be influenced by a number of factors including hormones, body size, tobacco smoke,
coffee intake, and cruciferous vegetables (Hong etl al, 2004).
Mutations in the CYP1A2 gene, particularly the single nucleotide polymorphism
(SNP) from adenine to cytosine at position 734 (1F allele) showed an increased risk of
non-fatal myocardial infarctions among those homozygous for the allele (Yang et al.,
2010). This mutation decreases the inducibilty of the CYP1A2 enzyme, leading to
impaired caffeine metabolism, and as a result, those homozygous for the CYP1A2*1A
allele (A/A), the wild type, are “rapid” caffeine metabolizers, while those homozygous for
the *1F allele (F/F) are considered, “slow” metabolizers (Sohemy et al., 2007).
CYP1A2 is located on chromosome 15q24.1 in humans, and has a close link
with CYP1A1 by sharing a common 5-flanking region (Zhou et al, 2010). Both CYP1A1