Florencia Maeva Pratto, Ph.D.

Gametes, such as sperm and eggs, are produced through meiosis. In this specialized type of cell division, a single round of DNA replication is followed by two successive rounds of chromosome segregation. In the first division, homologs (each parental chromosome) separate; in the second division, the sister chromatids segregate, resulting in four haploid daughter cells. The segregation of homologs poses a unique challenge because they must be physically connected for accurate segregation. The connection between homologs, in most mammals, is mediated by the deliberate introduction of hundreds of double-stranded breaks (DSBs) and their subsequent repair through homologous recombination. The cell needs to fine-tune the timing and placement of DSBs to avoid deleterious events, such as mutations or aneuploidies. 20% to 60% of human oocytes have a karyotypic defect, and errors in meiosis are responsible for at least half of clinically recognized miscarriages, as well as a spectrum of chromosomal birth defects in humans, such as Down syndrome.

The main focus of our research is to understand the multiple layers that shape the recombination landscape over size scales ranging from single nucleotides to whole chromosomes in the human and mouse germlines. To achieve this goal we use a combination of genetics, multi-omics analysis and microscopy. Successful meiosis requires the coordination of multiple cellular and molecular processes. Through this research program, I seek to advance our knowledge of a critical biological process at the core of modern genetics that profoundly affects human reproductive health and disease.

• Staff Scientist, NIDDK, NIH, 2016-2024
• Postdoctoral Fellow, NIDDK, NIH, 2007-2016
• Ph.D., Universidad Autonoma de Madrid, 2007
• B.S., Universidad de Buenos Aires, 2000