Generation of transgenic mouse mutants (deletions or point mutations) with ubiquitously expressed  or conditional gene defects by homologous recombination  in embryonic stem cells by pronuclear injection of DNA.

Knock-in mice with reporter genes coding for ß galactosidase or fluorescent proteins. Tamoxifen - or Doxycylin  inducible transgenic mice.

Sphingolipid analyses, histochemical analyses of various mouse tissues.