North Texas Girl First to Receive Cutting-Edge Treatment for Rare Genetic Disorder

An 11-year-old girl from Rowlett, Texas, is set to make medical history by becoming the first patient worldwide to undergo treatment for a rare genetic disorder known as NARS1. Marley Mansour was diagnosed early in 2023 after enduring years of unexplained health challenges. This rare condition affects the production of proteins within the body, leading to developmental delays, neurological issues, and motor skill difficulties.

Marley is among fewer than 100 individuals globally identified with NARS1, according to her healthcare team at UT Southwestern Medical Center. The innovative treatment she will receive is called antisense oligonucleotide (ASO) therapy, a form of genetic medicine that uses synthetic DNA strands to target and modify specific mRNA molecules, thereby correcting or mitigating the genetic defect.

The treatment is being developed by the nonprofit organization N-Lorem, based in California, which crafts personalized therapies for patients with ultra-rare diseases. For Marley, the therapy will focus on her unique genetic mutation, aiming to produce the necessary proteins to improve her communication abilities and reduce peripheral neuropathy.

Accessing the treatment requires a detailed application process whereby a research physician explains Marley's mutation to N-Lorem. The therapy will be administered via a spinal tap, with the goal of enabling her body to generate functional proteins. Marley’s mother, Kayla Mansour, expressed her concerns about her daughter’s inability to communicate pain or discomfort, emphasizing the importance of this groundbreaking treatment.

Scientifically, NARS1 encodes for asparagine-tRNA synthetase, a vital enzyme for protein synthesis. Mutations in this gene hinder the body's ability to produce proteins properly, resulting in a range of neurological and developmental issues. Marley's specific mutation produces a toxic version of the protein, complicating her condition. The ASO therapy aims to neutralize the defective RNA, thereby allowing healthy protein production.

This development marks a significant step forward in personalized medicine for ultra-rare genetic disorders. N-Lorem has already treated 15 patients and evaluated hundreds, focusing on safe and effective therapies. Despite the promise, the treatment costs approximately $1.2 million per dose, funded through donations, grants, and partnerships. The nonprofit has committed to covering the treatment costs lifelong, though Marley’s family will be responsible for related hospital expenses not covered by insurance.

This pioneering therapy not only offers hope for Marley but also sets a precedent for future treatments for other patients with similar genetic mutations. It highlights the growing potential of tailored genetic therapies in transforming lives affected by ultra-rare diseases.

For more information and to support Marley’s family, visit supportnow.org/marley-s-miracle.

Source: https://medicalxpress.com/news/2025-05-north-texas-girl-patient-treatment.html