An 11-year-old girl from Rowlett, Texas is poised to make medical history as the first person in the world to receive treatment for a rare genetic disorder called NARS1.
Marley Mansour, diagnosed in early 2023 after years of searching for answers, is one of fewer than 100 people globally identified with this condition. The rare genetic disorder affects protein production in the body, leading to significant developmental and neurological challenges.
"Communication is a big struggle for her; she can't converse with us," explained Kayla Mansour, Marley's mother. "She can't tell us where it hurts in her body… and that's one of the things we're terrified of. What if she can't tell us something hurts or something's wrong?"
The Breakthrough Treatment Approach
The experimental treatment Marley will receive is antisense oligonucleotide therapy (ASO), which uses short, synthetic DNA sequences to target specific messenger RNA (mRNA). California-based nonprofit organization n-Lorem is developing this personalized medicine specifically for Marley's genetic mutation.
Dr. Kaitlin Batley, an assistant professor of pediatrics and neurology at UT Southwestern Medical Center and Marley's physician, explained that the ASO will be administered through a spinal tap. The treatment is designed to help Marley's body produce the necessary proteins to address her communication difficulties and peripheral neuropathy.
The Science Behind NARS1
NARS1, short for asparagine-tRNA synthetase, plays a critical role in protein synthesis. Mutations in this gene disrupt the body's ability to produce proteins properly, resulting in various symptoms including developmental delays, seizures, and motor skill challenges.
Dr. Stanley Crooke, CEO of n-Lorem, explained the specific nature of Marley's condition: "She has a mutation that makes a protein worse for her. She has one good gene, one bad gene. That means she makes one good molecule of RNA and one bad molecule of RNA, one good molecule of protein, one bad molecule."
The ASO therapy will target and neutralize the defective RNA, allowing her healthy RNA to function correctly. This approach addresses the root cause of the disorder at the molecular level.
Pioneering Personalized Medicine
N-Lorem specializes in developing individualized ASO treatments for patients with ultra-rare conditions. According to their website, by 2022, the organization had helped 150 nano-rare patients, evaluated over 300 applications, accepted over 140 patients into its program, and had already treated 15 patients.
"We only work with what we know and are doing, and we are confident we can do what we need to do safely," Crooke stated. "A watchword for us is to not harm."
Each treatment costs approximately $1.2 million and is funded through donations, grants, and partnerships. While n-Lorem will cover the cost of Marley's treatment for life, her family is responsible for any clinical-trial-related hospital expenses not covered by insurance, which are expected to reach six figures over the two-year trial period.
Implications for Rare Disease Treatment
While Marley's treatment is specifically tailored to her genetic mutation, it sets an important precedent for other NARS1 patients with similar genetic profiles. This breakthrough could potentially pave the way for more accessible therapies for those with ultra-rare diseases.
The case highlights both the remarkable advances in personalized medicine and the ongoing challenges faced by families dealing with rare genetic disorders. Financial burdens remain significant, even with nonprofit support for the treatment itself.
For those wishing to support the Mansour family with their medical expenses, donations can be made through their Support Now page at supportnow.org/marley-s-miracle.
