Related Experiment Videos
Postnatal growth and behavioral development of mice cloned from adult cumulus cells
K L Tamashiro1, T Wakayama, R J Blanchard
1Bekesy Laboratory of Neurobiology, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
Abstract:
Since the first successful cloning of mammals from adult somatic cells, there has been no examination of the learning or behavior of cloned offspring. The possibility of adverse effects on animals produced through adult somatic cell cloning is high because many natural biological processes are bypassed and DNA from adult cells, which presumably contain mutations, are used. In this study, we compared cloned mice produced by microinjection transfer of cumulus cell nuclei into enucleated oocytes, to control mice that were specifically generated to eliminate confounding factors that are unique to our cloning procedure. Postnatal weight gain of clones was significantly greater than that of controls. Preweaning development observations revealed that first appearance or performance of 3 out of 10 measures was delayed in cloned mice; however, results of subsequent tests of learning and memory, activity level, and motor skills were comparable for both groups. Together, these data suggest that nuclear transfer of adult somatic cell nuclei to produce cloned mice may delay the appearance of a few developmental milestones but it does not adversely affect the overall postnatal behavior of mice. In addition, this procedure may cause late onset of significantly increased body weight in cloned offspring, the cause or causes of which are being further examined.
Insights
Cloned mice exhibited delayed developmental milestones but showed normal learning and behavior. Adult somatic cell cloning may increase body weight in offspring, warranting further investigation.
Area of Science:
- Animal cloning
- Developmental biology
- Behavioral science
Background:
- Mammalian cloning from adult somatic cells bypasses natural processes, raising concerns about offspring health.
- Previous studies have not assessed the learning or behavior of cloned animals.
Purpose of the Study:
- To compare the behavior and development of cloned mice with controls.
- To investigate potential adverse effects of adult somatic cell cloning on postnatal development and behavior.
Main Methods:
- Cloned mice were produced via microinjection of cumulus cell nuclei into enucleated oocytes.
- Control mice were generated to isolate cloning procedure variables.
- Developmental milestones, weight gain, learning, memory, activity, and motor skills were assessed.
Main Results:
- Cloned mice showed significantly greater postnatal weight gain compared to controls.
- A delay in 3 out of 10 preweaning developmental measures was observed in clones.
- Learning, memory, activity, and motor skills were comparable between cloned and control mice.
Conclusions:
- Adult somatic cell nuclear transfer may delay some developmental milestones but does not negatively impact overall postnatal behavior.
- Cloning procedures might lead to increased body weight in offspring, requiring further research.