PPP1R9A (protein phosphatase 1, regulatory subunit 9A; neurabin-1) was reported to show biased or
monoallelic expression in some tissues (tongue, eye, limb, placenta) in some embryos, but the
pattern was inconsistent within tissues and within embryos (Nakabayashi
K et al, 2004). Only one embryo was informative for isoform 1 (maternal expression in tongue and
eye) and two were informative for isoform 2 (maternal expression in tongue only in one, and placenta
only in the other)
In term placenta, PPP1R9A was biallelic in 5 samples (Monk
D et al, 2008).
The human PPP1R9A promoter CpG island did not show differential methylation (Nakabayashi
K et al, 2004).
Baran Y et al (2015) found no evidence of
imprinting in multiple adult tissues.
There is insufficient evidence to classify human PPP1R9A as imprinted.