TP73 (tumour protein p73) was reported to be maternally expressed in blood and some neuroblastoma
cell lines (Kaghad
M et al, 1997). Maternal expression has been confirmed in fetal pancreas and thymus and in adult
normal kidney and oesophagus (Mai
M et al, 1998; Cai
YC et al, 2000). Monoallelic expression was confirmed in peripheral blood (Martinez-Delgado
et al, 2002) and in 3 of 4 fetal brains, but biallelic expression was observed in all other
fetal tissues (Hu
JF et al, 2000).
No imprinting of TP73 was found in 27 of 29 lung specimens and in one case with allelic imbalance the
preferentially expressed allele was paternally derived (Nomoto
S et al, 1998). Variable imprinting was found in human placenta (Diplas
AI et al, 2009).
Biallelic expression of TP73 was found in 8 or 8 human embryonic stem cell lines (Kim
KP et al, 2007).
TP73 is located in the region showing preferential maternal loss of heterozygosity in neuroblastomas
without MYCN amplification (Caron
H et al, 1995), but some have argued against a role in neuroblastoma (Ejeskar
K et al, 1999). TP73 is a candidate tumour suppressor gene involved in lymphoma (Martinez-Delgado
et al, 2002).
Morcos L et al, (2011) found no evidence of
allelic expression bias in lymphoblast and fibroblast cell lines.