The PON genes (1-3) are closely related paralogs (65% amino acid similarity) located adjacently on
chromosome 7. These proteins have been associated with coronary heart disease.
Human PON2 is biallelically expressed in placenta and fetal tissues (Monk
D et al, 2008).
The mouse homologue Pon2
is preferentially maternally expressed in placenta and yolk sac samples (day 10 and 13 respectively)
R, et al. 2003).