Related Experiment Video
Updated: Jun 10, 2026

Contractility Measurements of Human Uterine Smooth Muscle to Aid Drug Development
Published on: January 26, 2018
Absence of mitochondrial progesterone receptor polymorphisms in women with spontaneous preterm birth
Tracy A Manuck1, Thomas M Price, Elizabeth Thom
1Eunice Kennedy Shriver NICHD MFMU Network, Bethesda, MD, USA. tracy.manuck@hsc.utah.edu
Objective:
The truncated mitochondrial progesterone receptor (PR-M) is homologous to nuclear PRs with the exception of an amino terminus hydrophobic membrane localization sequence, which localizes PR-M to mitochondria. Given the matrilineal inheritance of both spontaneous preterm birth (SPTB) and the mitochondrial genome, we hypothesized that (a) PR-M is polymorphic and (b) PR-M localization sequence polymorphisms could result in variable progesterone-mitochondrial effects and variable responsiveness to progesterone prophylaxis.
Methods:
Secondary analysis of DNA from women enrolled in a multicenter, prospective, study of 17 alpha-hydroxyprogesterone caproate (17OHPC) versus placebo for the prevention of recurrent SPTB. DNA was extracted from stored saliva.
Results:
The PR-M localization sequence was sequenced on 344 patients. Sequences were compared with the previously published 48 base-pair sequence, and all were identical.
Conclusions:
We did not detect genetic variation in the mitochondrial localization sequence of the truncated PR-M in a group of women at high risk for SPTB.
Related Concept Videos
Mitochondrial Precursor Proteins
Most of the mitochondrial precursors...
Animal Mitochondrial Genetics
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Mitochondrial Protein Sorting
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Teratogenicity
Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu