Some heritable but unstable genetic mutations that are passed from parent to affected offspring may not be easy to investigate using current human-induced pluripotent stem cell (hiPSC) modeling techniques, according to research conducted at The Icahn School of Medicine at Mount Sinai and published March 14, in the journal Stem Cell Reports. The study serves to caution stem cell biologists that certain rare mutations, like the ones described in the study, are difficult to recreate in laboratory-produced stem cells.