# Reciprocal restriction fragment length polymorphism (RFLP) analysis reveals mitochondrial heteroplasmy in Caenorhabditis briggsae hybrids

## TL;DR

This study uses a DNA analysis method to show that some hybrids of a worm species have mixed mitochondrial DNA from both parents.

## Contribution

The novel reciprocal RFLP analysis enables detection of paternal and maternal mitochondrial DNA in hybrids.

## Key findings

- Some hybrids of Caenorhabditis briggsae are heteroplasmous with both paternal and maternal mitochondria.
- Other hybrids have become homoplasmous for the paternal mitochondrial type.
- Paternal mitochondrial transmission appears common in C. briggsae hybrids.

## Abstract

Although mitochondria are typically inherited maternally, exceptions exist. We previously demonstrated that within-species crosses of

Caenorhabditis briggsae

result in paternal mitochondrial transmission, and it would be useful to know whether hybrids have only paternal mitochondria (homoplasmy) or paternal and maternal mitochondria (heteroplasmy). We developed a reciprocal restriction fragment length polymorphism analysis to separately detect paternal and maternal mitochondrial DNA. Using new hybrid lines, this approach revealed that some hybrids are heteroplasmous and others have become homoplasmous for the paternal mitotype. These results motivate additional investigation of how paternal mitochondrial transmission is apparently facile in

C. briggsae

.