Spinal Muscular Atrophy Genetic Counseling Access and Genetic Knowledge: Parents' Perspectives

Abstract

Spinal muscular atrophy is characterized by degeneration of α motor neurons in the anterior horns of the spinal cord, which leads to progressive symmetrical muscle weakness and atrophy. Spinal muscular atrophy is the leading fatal autosomal recessive disorder in infancy, and genetic counseling is an essential component of the care of families of these patients. However, little guidance is available in the published literature regarding the process and benefit of genetic counseling for families. Accordingly, the authors designed a questionnaire to assess parents' knowledge of the disease, gauge their access to genetic counseling, and determine how parents use information gained from counseling to guide choices for future pregnancies. The questionnaire specifically targeted when genetic counseling was received, from whom, parental knowledge regarding spinal muscular atrophy genetics, parental choices regarding spinal muscular atrophy and their child, frequency of prenatal testing, perceived relevance of newborn screening, and opinions regarding the disease. Most families clearly received some type of genetic counseling. Yet how and from whom they received the information varied greatly, as did their genetic knowledge of spinal muscular atrophy. The highest percentage of families received counseling from neurologists, who may not be appropriately prepared to provide formal genetic counseling. Many respondents reported having a negative experience with genetic counseling, possibly because it occurred at the time of diagnosis or shortly afterward, a period of great emotional turmoil. These data suggest that a consistent approach for facilitating how and when genetic counseling is received is greatly needed.

Keywords

spinal muscular atrophy genetic counseling genetic testing carrier testing parents' perspectives

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