High-throughput sequencing genetic testing identifies 25% more rare disease risks microbiologystudy

Rare diseases (RD) are more common than you might think. For every 20 people you know, one is likely affected by a rare disease. Of the 7,000 known RD conditions, 80% have a genetic origin, yet over 95% remain incurable. Preventive genetic testing offers families a powerful tool to make informed reproductive choices, potentially preventing these diseases before they manifest.

World Rare Disease Day is a time to raise awareness and encourage early recognition of symptoms. Deepening the public’s understanding of rare diseases can help medical practitioners and caregivers recognize that common symptoms might be due to rare diseases. With the support of genetic testing tools, this early recognition allows patients to receive precise and timely treatment.

A devastating diagnosis: Liz Taylor’s story

Imagine living a healthy life only to discover a hidden genetic flaw that could alter your family’s future. This was Liz Taylor’s reality, as her family told BBC News.

In her late 30s, she was active and healthy until persistent hand pain led to a life-changing diagnosis. Her doctor recommended genetic testing, revealing she had neuroferritinopathy (NF), a rare genetic disorder that causes iron to build up in the brain, damaging neurons and leading to a loss of mobility, speech, and the ability to eat.

Now at 59, Liz can only communicate with her family through eye movements. Tragically, three of her sisters also have NF, and Liz’s daughter, Penny, now fears she may be next. Fewer than 100 cases of NF are known worldwide, and before its identification in 2001, it was often misdiagnosed as Parkinson’s or Huntington’s disease. The true tragedy is not just the lack of effective treatment, but the missed opportunity for prevention.

Complex nature of rare diseases

Early detection of RD is crucial, yet the path to diagnosis is often long and uncertain. A survey by the European Organisation for Rare Diseases (EURORDIS) revealed that on average, patients wait almost 5 years from the onset of symptoms to receive a correct diagnosis.

Many RD mimic more common conditions, leading to years of misdiagnosis before the true cause is found. For example, Ehlers-Danlos Syndrome (EDS), a genetic disorder affecting connective tissues, is often misdiagnosed as fibromyalgia or arthritis due to overlapping symptoms like joint hypermobility and skin fragility.

Many patients are misdiagnosed multiple times, consulting with several doctors before the truth emerges. Children are especially vulnerable; half of all RD patients are under 18, and 30% of them die before their fifth birthday.

Prevention over treatment—the Chu family’s story

In a small home in Vietnam, the Chu family faced an agonizing mystery. Two young brothers, Chu Nam Phong and Chu Nam Khánh, had struggled with severe muscle weakness since birth. Their parents sought help from multiple hospitals, but no diagnosis was forthcoming.

“I was frustrated,” their mother said. “I didn’t know how to help my children. We could only try our best every day, hoping for a miracle.”

The breakthrough came with the Whole Exome Sequencing (WES), a cutting-edge genetic test provided by BGI Genomics. By analyzing the children’s DNA, scientists discovered a mutation in the CHKB gene, responsible for Megaconial Muscular Dystrophy, an ultra-rare disease that weakens muscles to the point of immobility.

“I would advise families facing genetic conditions to get genetic testing done to identify the cause of the illness,” the mother shared.

With this newfound knowledge, the family made a crucial decision. They turned to in vitro fertilization (IVF) and preimplantation genetic testing (PGT), a procedure that allowed them to select embryos free of the disease-causing genetic mutation. Their next child was born healthy, free from the disease that had affected the Chu brothers.

Genetic testing reduces RD-related birth defects

Across the globe, countless families unknowingly carry genetic risks hidden within their DNA. A 2022 study published in Human Genomics examined genetic risks among couples in southern and southwestern China. Through the use of genetic testing, researchers found that 1 in 12 couples carried high-risk recessive genetic mutations, with a 25% chance of passing these conditions to their children. With the support of genetic screening, these risks have been revealed and led to a more detailed diagnosis for the couple and fetus.

Advances in genetic testing provide families with opportunities to make informed decisions before disease symptoms appear. Expanded Carrier Screening (ECS) and Whole Exome Sequencing (WES) can now detect 25% more disease-causing mutations than traditional screening methods. Unlike older techniques that focus on common mutations, high-throughput sequencing (HTS) offers a more comprehensive analysis, identifying rare genetic variants that may otherwise go undetected.

Genetic testing is not just a tool for diagnosis; it is a lifeline that offers families the power to prevent the devastating impact of rare diseases. By using genetic screening technologies like WES and ECS, families can make informed decisions, safeguard their children’s health, and in some cases, break the cycle of genetic disease before it begins.

Provided by
BGI Genomics