Spina bifida as a multifactorial birth defect: Risk factors and genetic underpinnings

Abstract

Spina bifida is a birth defect resulting from abnormal embryonic development of the neural tube. Though spina bifida is divided into several subtypes, myelomeningocele—the most severe form of spina bifida often associated with a markedly diminished quality of life—accounts for a significant portion of cases. A broad range of genetic and environmental factors, many of which are still unknown, influence spina bifida, making it difficult to provide a comprehensive etiology for the disorder. Folic acid supplementation aided by the mandatory fortification of food is preventive; still, spina bifida persists due to numerous other confounding factors that affect risk. This article reviews the latest studies pertaining to the risk factors and genetics involved in spina bifida in an attempt to elucidate the complex background of the congenital malformation. Additionally, this review highlights the significant impact of environmental pollutants, adverse medication effects, and maternal health conditions such as diabetes and obesity on the prevalence of spina bifida. Emerging research on gene-environment interactions provides insight into how specific genetic variants may influence susceptibility to these environmental factors. We also discuss new technologies in genetic sequencing that show promise for the large-scale discovery of genes associated with spina bifida risk. Understanding these intricate interactions is crucial for developing effective prevention and intervention strategies.

Keywords

genetics / neural tube defects / risk factors / spina bifida / spinal dysraphism

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