Scientists Identify Two Genes Essential for Breathing

A team of researchers at the New York University’s Langone Medical Center has discovered that two genes, called Hoxa5 and Hoxc5, play a critical role in establishing the neuronal circuits required for breathing. The discovery could help advance treatments for spinal cord injuries and neurodegenerative diseases.

The three-year study published in the journal Nature Neuroscience identifies a molecular code that distinguishes a group of muscle-controlling nerve cells collectively known as the phrenic motor column (PMC).

“These cells lie about halfway up the back of the neck, just above the fourth cervical vertebra, and are probably the most important motor neurons in your body,” explained senior author Prof Jeremy Dasen of the Howard Hughes Medical Institute.

Harming the part of the spinal cord where the PMC resides can instantly shut down breathing. But relatively little is known about what distinguishes PMC neurons from neighboring neurons, and how PMC neurons develop and wire themselves to the diaphragm in the fetus. The PMC cells relay a constant flow of electrochemical signals down their bundled axons and onto the diaphragm muscles, allowing the lungs to expand and relax in the natural rhythm of breathing.

“We now have a set of molecular markers that distinguish those cells from other populations of motor neurons, so that we can study them in detail and look for ways to selectively enhance their survival,” Prof Dasen said.