Components that may lead to a diagnosis include the presence of clinical symptoms, evidence of degeneration, and analysis of family history. One notable sign of SMAX2 is the loss of anterior horn cells in the<unk>  cord and brain stem. SMAX2 is typically confirmed through genetic testing that shows a mutation in the ubiquitin-like modifier-activating enzyme 1 gene (UBA1). The UBA1 gene is important to diagnosis as it is the only gene known to correspond with degeneration of<unk> L-SMA. In infancy it is important to look for the following when considering a<unk><unk><unk>  muscular<unk>  diagnosis: * Congenital hypotonia and areflexia on physical examination * Congenital contractures/fractures * Digital contractures at birth that remain throughout the child's life * Evidence of degeneration and loss of anterior horn cells (i.e., lower motor neurons) in the<unk>  cord and brain stem A child with these symptoms are likely to have<unk><unk><unk>  muscular<unk> . In order to confirm this the most practical measures to take next are: * to perform a normal SMN1 molecular genetic testing to rule out autosomal recessive<unk>  muscular<unk>  * perform an analysis to see if it is male gender in a simplex case (i.e., a single occurrence in a family) or find the presence of<unk><unk>  pattern of inheritance in families with more than one affected individual
X-linked spinal muscular atrophy type 2
Jokela type spinal muscular atrophy
Fukuyama congenital muscular dystrophy
Distal spinal muscular atrophy type 2
Ullrich congenital muscular dystrophy
Distal spinal muscular atrophy type 1
Madras motor neuron disease
Becker muscular dystrophy