The Col4a2em1(IMPC)Wtsi mouse line: lessons from the Deciphering the Mechanisms of Developmental Disorders program.

The Deciphering the Mechanisms of Developmental Disorders (DMDD) program uses a systematic and standardised approach to characterise the phenotype of embryos stemming from mouse lines, which produce embryonically lethal offspring. Our study aims to provide detailed phenotype descriptions of homozygous Col4a2em1(IMPC)Wtsi mutants produced in DMDD and harvested at embryonic day 14.5. This shall provide new information on the role Col4a2 plays in organogenesis and demonstrate the capacity of the DMDD database for identifying models for researching inherited disorders. The DMDD Col4a2em1(IMPC)Wtsi mutants survived organogenesis and thus revealed the full spectrum of organs and tissues, the development of which depends on Col4a2 encoded proteins. They showed defects in the brain, cranial nerves, visual system, lungs, endocrine glands, skeleton, subepithelial tissues and mild to severe cardiovascular malformations. Together, this makes the DMDD Col4a2em1(IMPC)Wtsi line a useful model for identifying the spectrum of defects and for researching the mechanisms underlying autosomal dominant porencephaly 2 (OMIM # 614483), a rare human disease. Thus we demonstrate the general capacity of the DMDD approach and webpage as a valuable source for identifying mouse models for rare diseases.