# Mapping-by-Sequencing via eBSRmap (Easy Bulk Segregate RNA Mapping) in a B73 EMS Mutant Population

## TL;DR

This paper introduces eBSRmap, a cost-effective method for identifying genes responsible for maize kernel traits using RNA sequencing in a mutant population.

## Contribution

The novel eBSRmap method simplifies gene mapping in maize by combining RNA-seq with bulk segregant analysis in an EMS mutant population.

## Key findings

- eBSRmap identified candidate genes for twenty kernel trait mutants, with twelve successfully mapped.
- Eight genes were confirmed by co-segregation analysis, showing a 40% success rate.
- Mutations included missense and stop-gained variants linked to kernel phenotypes like shrinkage and defects.

## Abstract

Background: Maize, crucial for food, feed, and industry, is a model for genetic and breeding research. Kernel traits directly affect maize yield. This study developed the eBSRmap method to simplify gene cloning related to maize kernel traits. Methods: The eBSRmap method constructs a maize EMS mutant population, then conducts RNA-seq on pooled mutant and wild-type samples to identify SNP markers and map candidate genes for kernel trait mutations. Results: Applied to a maize EMS mutant population, eBSRmap identified candidate genes for twenty kernel trait mutants, successfully mapped twelve, and eight were confirmed by co-segregation analysis (success rate: 40%). The identified genes showed mutations like missense and stop-gained, related to phenotypes such as small, shrunk, and defective kernels. Conclusions: eBSRmap offers a fast and affordable way to map genes and identify candidate genes in a large-scale mutant population, aiding the understanding of gene functions in maize. The identified candidate genes can be further validated by functional analysis, which is significant for maize breeding and genetic improvement.