# Deletion of Kallikrein-related peptidases ( Klks ) has no effect on fertility in mice

## TL;DR

Deleting four kallikrein-related peptidase genes in mice did not affect fertility or health, suggesting these genes are not essential for reproduction.

## Contribution

Generated a mouse model with deletions of four Klk genes and demonstrated their non-essential role in fertility.

## Key findings

- Male and female knockout mice were fertile with no health defects.
- The Klk1b3, Klk1b4, Klk1b5, and Klk1 genes are not required for reproductive function in mice.

## Abstract

Kallikreins (KLKs) are serine peptidases. It was established that
Klks
are estrogen-target genes in mouse uteri. However, the functional requirement of KLK family in the uterine function during reproduction is unknown. Here we generated a compound deletion of
Klk1b3, Klk1b4, Klk1b5,
and
Klk1
in a mouse model using CRISPR/Cas9 strategy with four single guide RNAs (sgRNAs) to target the second exon of these four genes that are aligned back-to-back in a single locus spanning 32.95 kb on chromosome 7. We found that both male and female knockout mice are fertile with no apparent health defect compared to wild-type controls. Our data suggest that
Klk1b3, Klk1b4, Klk1b5,
and
Klk1
are not necessary for male and female reproductive function in mice.