Mouse Genome Informatics
involves: 129/Sv * C57BL/6
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
• homozygous mutant embryos at E7.5 and at E8.0 were morphologically abnormal and severely growth retarded
• by E9.5, homozygous mutant embryos were degenerating, and no homozygous mutant progeny were seen in heterozygote intercrosses

• at E7.5, embryonic and extraembryonic ectoderm separated by a groove
• some mesoderm cells found between ectoderm and visceral endoderm
• markedly disorganized, does not form a node and fails to produce mesendoderm and embryonic mesoderm
• anteroposterior axis is not specified
• absence of typical egg cylinder shape at E6.5
• ectoderm did not exhibit its characteristic groove and always showed an abnormally large gap
• numerous dying cells with pyknotic nuclei detected on each side of the gap and within the proamniotic cavity
• no headfolds, allantois and proamniotic cavity remain undivided
• embryos with amniotic folds and with proamniotic cavity divided into 3 compartments but indications of apoptosis also appearing

Mouse Models of Human Disease
NOT Sotos Syndrome 1; SOTOS1 117550 J:83923