The Role of Genetic Counselling in the Prevention and Management of Inborn Errors of Metabolism: A Review

Abstract

Inborn errors of metabolism (IEMs) are a heterogenous set of inherited illnesses that occur due to abnormalities in enzymes, transport proteins, cofactors or other components of metabolic pathways. Rare separately, together IEMs contribute substantially to infant morbidity, developmental disability, neurological dysfunction, metabolic crises, organ damage and early mortality. Many IEMs are curable and early detection and immediate care can avert irreparable sequelae. Genetic counselling is a major component of the continuum of care for IEM, from preconception risk assessment and carrier discovery to newborn screening, molecular diagnosis, prenatal diagnosis, reproductive decision-making, therapeutic education, cascade testing and psychosocial support. Improvements in tandem mass spectrometry, next-generation sequencing, whole-exome sequencing, whole-genome sequencing, and metabolomics have promoted early detection and diagnosis. However, these technologies also pose issues in the interpretation of variants of unknown importance, informed consent, privacy, incidental results, affordability and equal access. These difficulties are especially pertinent in low- and middle-income countries, such as Nigeria, where newborn screening programs, specialised metabolic laboratories, genetic counselling services and access to treatment are still limited. Recent research from throughout Africa points to considerable variation in newborn screening and the need for integrated systems that link screening to confirmatory diagnosis, treatment, counselling and follow-up. The study highlights the significance of genetic counselling in the prevention and management of IEMs and methods for strengthening genetic and metabolic services in Nigeria and other resource-limited