A tablet taken by mouth, it causes the body to boost the activity of a second gene, called SMN2, which also carries the instructions for building SMN protein but typically makes less than SMN1. Until ...

SMA is caused by reduced levels of survival motor neuron (SMN) protein due to deletions or mutations of the SMN1 gene. A nearly identical gene, SMN2, produces low levels of functional SMN protein.

A child with a rare genetic disorder — spinal muscular atrophy type I — was treated prenatally for the first time. Courtesy of Jakob Owens  via Unsplash During an amniocentesis test, a long, thin ...

In general, each corresponds to the copy number of the SMN2 gene, which produces a small fraction (~10%) of functional SMN protein, essential to the survival of motor neurons, compared with SMN1.

In its most severe form, as in the case of this child, individuals lack both copies of the SMN1 gene, and have only one or two copies of a neighbouring gene, SMN2, that partially compensates for ...