Birth of spinal muscular atrophy unaffected baby from genetically at-risk parents following a pre-implantation genetic screening: A case report


Background: Spinal muscular atrophy (SMA) is characterized by the homozygous deletion of the survival motor neuron-1 gene. Pre-implantation genetic testing for monogenic diseases through in-vitro fertilization program was developed to provide a reliable genetic diagnostic method for SMA.

Case presentation: The couple who was confirmed as carriers of SMA visited the Morula IVF Clinic, Jakarta, Indenesia seeking for an in-vitro fertilization expert opinion in relation to the pre-implantation genetic testing for SMA. Utilizing polymerase chain reaction-restriction fragment length polymorphism, we have successfully screened for unaffected embryos that were characterized by a normal presence of the survival motor neuron-1 exon 7-8 and survival motor neuron-2 exon 7-8. The frozen embryo was subsequently transferred and a healthy unaffected female baby was born with undetected deletion of the survival motor neuron-1 gene.

Conclusion: This successful embryo pre-implantation screening case could potentially accommodate the demands of genetically at-risk couples who are apprehensive about conceiving a child who might inherit monogenic disorders such as SMA.

Key words: In-vitro fertilization, Spinal muscular atrophy, Preimplantation diagnosis.

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