USC stem cell researchers have completed their analysis and in-depth deconstruction of the kidney to highlight the key differences in the organ between males and females. This notion of sexual diversity comes as a historic distinction, as previous studies have relied solely on male data to be applied to the kidneys of both sexes.

Kidney disease affects 15% of U.S. adults, according to the Centers for Disease Control and Prevention, with differences that manifest through ethnic and sex-related susceptibility to both kidney injury and disease. The new research illuminates sex-related organ differences that will help doctors locate genes linked to disease. It also assists in the reprogramming of DNA which will allow the manipulation of cells to create tissue that was damaged or lost because of disease.

The research, published Nov. 4, was led by Andrew McMahon, Chair of the Department of Stem Cell Biology and Regenerative Medicine at the Keck School of Medicine.

McMahon expressed how former kidney studies have used data from male subjects and employed said data to female counterparts. This new study puts sexual diversity at the cell level at the forefront of future research, according to McMahon.

“Over the years the modeling of disease has preferentially used male based animal models, and now it’s a national priority to include both male and female,” McMahon said. “We’ve been looking in detail at the single cell level to identify the whole gene repertoire of every cell within the kidney and the remarkable diversity between the two sexes in the gene activities within certain cell types of the kidney.”

McMahon credits technological innovation as the catalyst for the implementation of sexual distinction within the study of kidneys.

“It largely relates to technological developments including the approach that enables you to take a whole organ system and break it down to single cells,” McMahon said. “Then to identify genes that are present and expressed within the cells and what we’ve done, which I think is a little bit more distinct from other people is to build that back into the organization of the organ system."

In their study, USC stem cell researchers have focused their work on examining the kidneys of mice, which translate easily into human findings. McMahon detailed that his team needs to further investigate which findings soundly apply to humans.

“We know there is sexual diversity in the case of the mouse, but we don’t know if there’s sexual diversity for all of these genes in the case of the human,” McMahon said. “By knowing what that sex diversity is in case of a human kidney, then we can know best how to understand that using the mouse model system.”

On top of published research, McMahon and his team created the online database Kidney Cell Explorer. This database is designed to help researchers quickly identify sexual differences in kidney cells and determine links among genes, cells and disease.