Placental gene expression of transforming growth factor beta 1 (TGF-β1) in small for gestational age newborns

The gene expression of transforming growth factor beta-1 (TGF-β1) in human placental samples obtained from pregnancies with small for gestational age fetuses (SGA) was compared to those of normal pregnancies.

In 2011 placental samples from 101 pregnancies with SGA and from 140 normal pregnancies were obtained for analysis of TGF-β1 gene expression. Several clinical parameters were also assessed for correlation between genetic and clinical parameters.

There were no significant differences in gene activity of the TGF-β1 gene between the SGA versus normal pregnancy groups (Ln2α: 0.16; p = 0.07). Within the SGA group, no fetal gender-dependent differences were seen in TGF-β1 gene expression (Ln2α: −0.11; p = 0.05). Similarly, no significant differences in gene activity were observed by the degree of severity of SGA as assessed by percentile fetal birth-weight (Ln2α: 0.32; p = 0.06).

We found no change in gene expression of TGF-β1 in placental samples obtained from SGA pregnancies versus normal pregnancy suggesting an absence of a direct role of the TGF-β1 gene in the development of SGA. However, the absence of increased gene expression of TGF-β1 in SGA can be conceptualized as a failure to mount a compensatory response in the SGA environment.