7% of Mouse Genes Break Rules

A team led by researchers at the Johns Hopkins School of Medicine has found that several inherited traits in the mouse genome break the rules of traditional genetics. The study found that around 93% of methylation patterns in mice followed Mendel's rules, while around 7% did not. This discovery was made using a technology called nanopore sequencing, which allows for the study of epigenetic inheritance in mice.

The researchers identified over 500 instances of non-Mendelian epigenetic inheritance in mice. This means that the genes are not inherited in the traditional manner, where one copy is inherited from each parent. Instead, the genes are influenced by chemical modifications that can jump across generations and change depending on whether an animal is male or female.

In a separate study, researchers in Pakistan identified 'human knockouts' where individuals have genes that are naturally switched off. The study found that around one in five participants carried at least one gene with loss-of-function variants that had disrupted both copies. This means that the genes are not functioning, but the individuals are still able to live normal lives.

The study in Pakistan identified such knockouts across 6,476 genes, which is close to one-third of the roughly 20,000 protein-coding genes in humans. This discovery provides researchers with a unique opportunity to study the effects of gene knockouts in humans. Consanguineous marriages are common in several Pakistani communities, with nearly two-thirds of marriages between relatives and almost half between first cousins.

## Why it matters The findings of these studies have significant implications for human health. The discovery of non-Mendelian epigenetic inheritance in mice suggests that the same mechanisms may also shape human health, and be able to explain conditions that have long resisted genetic analysis. The identification of 'human knockouts' in Pakistan provides researchers with a valuable resource to study the effects of gene knockouts in humans.

The study of epigenetic inheritance and gene knockouts can help researchers to better understand the complexities of human genetics and develop new treatments for diseases. The use of nanopore sequencing technology has allowed researchers to study epigenetic inheritance in mice, and the discovery of 'human knockouts' in Pakistan has provided a unique opportunity to study the effects of gene knockouts in humans.

## What happens next The findings of these studies will likely lead to further research into the mechanisms of epigenetic inheritance and gene knockouts. Researchers will likely use the discovery of 'human knockouts' in Pakistan to study the effects of gene knockouts in humans and develop new treatments for diseases. The use of nanopore sequencing technology will likely become more widespread, allowing researchers to study epigenetic inheritance in other organisms and gain a better understanding of the complexities of genetics.