New Study Reveals Whole Genome Sequencing Benefits for Diagnosing Genetic Disorders in Newborns and Infants
Early detection and diagnosis of inherited conditions in newborns and infants are crucial for effective therapies and better health outcomes. With the advancement of targeted treatments like gene and cell therapies, the implementation of newborn DNA sequencing has become increasingly urgent. In a recent national study conducted by Tufts Medical Center in Boston, whole genome sequencing (WGS) has been found to be significantly more effective than targeted gene sequencing at identifying abnormalities responsible for genetic disorders in newborns and infants.
The study took place at six hospitals in the United States from June 2019 to November 2021, enrolling 400 newborns and infants under the age of one year with suspected undiagnosed genetic disorders. Each participant received both whole genome sequencing, which can identify variants in all 20,000 genes in the human body, and a targeted gene sequencing test called NewbornDx, which focuses on identifying variants in 1,722 genes linked to genetic disorders in this population.
The findings of the study revealed that whole genome sequencing detected a genetic disorder in 49% of patients, while the targeted gene sequencing test identified abnormalities in only 27% of study participants. Moreover, the targeted panel missed 40% of the diagnoses that whole genome sequencing captured. Additionally, the researchers discovered 134 new genetic diagnoses that had never been described before. Overall, 51% of patients in the study were diagnosed with a genetic disorder using either test.
These results demonstrate the superiority of whole genome sequencing in accurately diagnosing genetic disorders in newborns and infants. Another study conducted by researchers from Mass General Brigham and Boston Children’s Hospital also concluded that screening apparently healthy newborns using whole genome sequencing allowed entire families to become aware, for the first time, of dangerous but treatable genetic variants.
Despite the significant benefits of whole genome sequencing, there are various barriers and ethical concerns surrounding its widespread implementation. One key obstacle is the higher cost of whole genome sequencing compared to the targeted test. Healthcare payers may hesitate to bear these expenses, potentially leading to equity issues. However, it is important to consider that the costs associated with a prolonged diagnostic process later in life for children with rare inherited conditions may prove even more burdensome and detrimental to families’ well-being.
Another important aspect to consider is that targeted gene sequencing only screens for specific genetic disorders that appear in newborns and infants. In contrast, whole genome sequencing may inadvertently unveil potential health risks later in life, such as Alzheimer’s disease or cancer, that the child or their parents may not wish to know. The knowledge of being predisposed to an incurable disease could result in lifelong anxiety and distress without the possibility of intervention. There are also longstanding ethical questions regarding informed consent and data privacy for both the child and the parents.
The study also shed light on the lack of standardization in interpreting neonatal genetics. In 40% of cases, different laboratories disagreed on whether a mutually acknowledged gene abnormality was the cause of the suspected genetic disorder in the newborn or infant. This uncertainty can create challenges in determining the most appropriate diagnosis, therapy, and follow-up.
To ensure that vulnerable populations, such as newborns and infants with genetic disorders, receive optimal care, it is crucial to continue exploring the potential benefits, drawbacks, and ethical concerns of genome sequencing. Addressing these concerns will pave the way for improved diagnostic accuracy and better health outcomes.
In conclusion, the recent study highlights the superiority of whole genome sequencing in identifying genetic disorders in newborns and infants compared to targeted gene sequencing. However, the implementation of whole genome sequencing on a broader scale faces challenges such as cost, potential long-term health risks, and ethical considerations. Standardization of neonatal genetics interpretation is also an area that requires further attention. By addressing these issues, healthcare professionals can ensure that newborns and infants receive the best possible care and pave the way for advancements in genetic disorder diagnosis and treatment.
