Related Experiment Video
Updated: May 29, 2026

Mouse In Vivo Placental Targeted CRISPR Manipulation
Published on: April 14, 2023
The growth hormone receptor gene deleted for exon three (GHRd3) polymorphism is associated with birth and placental
Raja Padidela1, Sinead M Bryan, Sayeda Abu-Amero
1Developmental Endocrinology Research Group, UCL Institute of Child Health, University College London, London, UK.
Context:
Human growth hormone receptor (GHR) transcripts have two isoforms, full-length (GHRfl) or exon 3 deleted (GHRd3). An association of these isoforms has been found with small for gestational age (SGA) infants but does not influence adult height. The role of this polymorphism in the birth size spectrum in the general population is unclear.
Objective:
To determine the association of maternal and infants GHR exon 3 polymorphism with antenatal growth, birth size and early postnatal growth in two large, normal white European birth cohorts.
Study Design:
Pregnant women from white European families were recruited by the University College London Foetal Growth Study (n = 774) and the Moore normal pregnancy cohort (n = 274). GHR variants, wild-type (fl) and deleted for exon 3 (d3) were analysed using multiplex PCR.
Results:
There was a significant underrepresentation of infants wild-type fl/fl (36%) and overrepresentation of d3/d3 (14%) genotypes in the SGA infants within the cohorts (χ(2) = 11·2, P = 0·003, df = 2). Fl/fl was overrepresented in large for gestational age (LGA) infants (χ(2) = 6·1, P = 0·047, df = 2). There was a significant association of infants GHR isoforms with placental weight (P < 0·001) and birth weight standard deviation scores (P = 0·04) with the fl/fl genotype associated with a larger placental and birth weight. In multiple regression analysis, the GHR isoform type, maternal booking weight and parity influenced placental weight (R(2) = ·35; P < 0·001, df = 7). The GHR isoform type was not related to antenatal anthropometric measurements or growth in infancy.
Conclusion:
These data suggest that the GHR isoforms are associated with placental and birth weight.
Related Concept Videos
Genomic Imprinting and Inheritance
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...
Gonadal and Placental Hormones
In males, testosterone is the primary gonadal androgen. It plays a central role in the maturation of male reproductive organs — the penis and testes. Additionally, testosterone is instrumental in the development of secondary sexual characteristics — a deep voice as well as facial and pubic hair growth — and...
Polygenic Traits
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Teratogenicity
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
