Mouse Gestation Length Is Genetically Determined

Abstract

BackgroundPreterm birth is an enormous public health problem, affecting over 12% of live births and costing over $26 billion in the United States alone. The causes are complex, but twin studies support the role of genetics in determining gestation length. Despite widespread use of the mouse in studies of the genetics of preterm birth, there have been few studies that actually address the precise natural gestation length of the mouse, and to what degree the timing of labor and birth is genetically determined.Methodology/Principal FindingsTo further develop the mouse as a genetic model of preterm birth, we developed a high-throughput monitoring system and measured the gestation length in 15 inbred strains. Our results show an unexpectedly wide variation in overall gestation length between strains that approaches two full days, while intra-strain variation is quite low. Although litter size shows a strong inverse correlation with gestation length, genetic difference alone accounts for a significant portion of the variation. In addition, ovarian transplant experiments support a primary role of maternal genetics in the determination of gestation length. Preliminary analysis of gestation length in the C57BL/6J-Chr#A/J/NaJ chromosome substitution strain (B.A CSS) panel suggests complex genetic control of gestation length.Conclusions/SignificanceTogether, these data support the role of genetics in regulating gestation length and present the mouse as an important tool for the discovery of genes governing preterm birth.

Loss of Glycogen Synthase Kinase 3 Isoforms During Murine Oocyte Growth Induces Offspring Cardiac Dysfunction1

“…In our breeding colony controls, the cumulative death rate of offspring within 24 h of birth was 9% 6 3% and was comparable to previous reports for C57/B16 dams (5% 6 6%) [53]. Similarly, low offspring 24 h death rate was observed when dams were Gsk3a À/À b f/f (4% 6 2%) or oGsk3a þ/þ b À/À (5% 6 2%).…”

“…Inbred C57BL/6J and FVB/NJ mouse strains produce litters with 8 6 2 and 9 6 2 offspring, respectively [53]. Similarly, our mouse breeding colony produced 9 6 0.5 offspring/litter.…”

PDK4 Inhibits Cardiac Pyruvate Oxidation in Late Pregnancy

“…We used a late-pregnancy model in C57Bl/6 mice. Gestation typically lasts 19±0.5 days in this strain 16 , so we chose day 18 as representative of late pregnancy (LP). Morphometric analysis showed that at day 18, an approximately 13% increase in heart weight to tibia length ratios (HW:TL) is observed (Figure 1A), consistent with what has been found in previous studies and indicative of physiological hypertrophy.…”

Exploring the Potential Role of Inflammation as an Etiological Process in ASD

“…Gestational days 10.5, 12.5, and 14.5 for mouse pups seem to have particular implications on the offspring later in life, showing a wider range of ASD-like behaviors, such as more stereotypic behavior and less sociability (Bunting et al 2011). The typical gestational period for mice spans approximately 18-22 days (Murray et al 2010). Specifically, it appears that susceptibility during the second and third trimesters is critical to later atypical behavioral manifestation.…”