[3] After earning her doctorate she moved to the Johns Hopkins School of Medicine, where she was part of the cellular and molecular biology programme.
The mouse models developed by Tilghman and Bartolomei helped to identify that it was genetic mutations on H19 that cause Silver–Russell syndrome.
As a postdoc Bartolomei showed that DNA methylation was essential in conferring the parental identity of imprinted genes.
She dedicated her career to understand genomic imprinting, an inheritance process that results in unequal expression of the maternal and paternal alleles of genes.
These mouse models allowed Bartolomei to identify that assisted reproductive technologies (including in-vitro culture, embryo transfer, in vitro fertilisation and hormonal hyperstimulation) can contribute to errors in epigenetic gene regulation.