Death before birth: clues from gene knockouts and mutations
1Developmental Biology Unit, University of London, UK.
Trends in Genetics : TIG
|March 1, 1995
Summary
Surprisingly few mouse developmental disturbances cause embryonic lethality. Essential processes include vascular circulation, nutrient transfer, and hematopoietic transition, while many organ systems are non-essential in utero.
Area of Science:
- Developmental Biology
- Genetics
- Embryology
Background:
- Prenatal lethality in mouse models results from gene knockouts, insertions, or mutations.
- Understanding critical developmental pathways is key to identifying causes of embryonic death.
Purpose of the Study:
- To survey mouse gene mutations causing prenatal lethality.
- To identify essential versus non-essential developmental processes for early embryonic survival.
Main Methods:
- Analysis of existing data on mouse gene knockouts, transgene insertions, and spontaneous mutations.
- Categorization of lethal developmental disturbances based on affected systems and processes.
Main Results:
- Few developmental disturbances lead to embryonic or early fetal death.
- Essential processes include establishing vascular circulation, yolk-sac to liver hematopoiesis transition, implantation, and placental formation.
- The central nervous system, gut, lungs, urogenital, and musculoskeletal systems show little to no survival value in utero.
Conclusions:
- Embryonic survival is critically dependent on a limited set of developmental events.
- Many organ systems develop without immediate survival value during early gestation.
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