Related Experiment Videos
The Sp4H deletion may contain a new locus essential for postimplantation development
J Fleming1, A Pearce, S D Brown
1MRC Institute of Hearing Research, University Park, Nottingham, NG7 2RD, United Kingdom.
Genomics
|June 1, 1996
Summary
The Sp4H mutation in mice causes early embryonic death, likely due to deletion of a crucial gene beyond Pax3. This research investigates the genetic basis of this developmental defect in mouse embryos.
Area of Science:
- Developmental Biology
- Genetics
- Mouse Models
Background:
- The Sp4H mutation in mice is associated with white spotting in heterozygotes.
- The entire coding region of the Pax3 gene is deleted in Sp4H mutants.
- The embryonic lethality of Sp4H homozygotes has not been previously determined.
Purpose of the Study:
- To investigate the developmental fate of Sp4H homozygous mouse embryos.
- To precisely map the extent of the genetic deletion in Sp4H mutants.
- To identify potential additional genes deleted in Sp4H that may cause embryonic lethality.
Main Methods:
- Genotyping of embryos from Sp4H heterozygous matings using Southern blot and PCR.
- Histological analysis of resorption sites to determine developmental stage at arrest.
- Deletion mapping using flanking markers and linkage analysis in an intraspecific backcross.
Main Results:
- No Sp4H homozygous embryos were detected between embryonic days 9 and 13.
- Increased resorption sites were observed in Sp4H heterozygous matings, indicating embryonic lethality.
- Developmental arrest occurred before gastrulation, and the deletion spans at least 1.53 cM, encompassing Pax3 and four other markers.
Conclusions:
- Sp4H homozygous embryos exhibit early postimplantation lethality.
- The deletion in Sp4H is large enough to potentially include other genes besides Pax3.
- Another deleted gene, in addition to Pax3, is likely responsible for the embryonic lethality observed in Sp4H mutants.