About 10 to 16 out of every 100,000 children are born with SMA.
Spinal muscular atrophy (SMA) most often affects babies and children and makes it hard for them to use their muscles. When your child has SMA, there's a breakdown of the nerve cells in the brain and spinal cord. The brain stops sending messages that control muscle movement. Type 1. This is the most severe type of SMA. He may not be able to support his head or sit without help. He may have floppy arms and legs and problems swallowing. The biggest concern is weakness in the muscles that control breathing. Most children with type 1 SMA don't live past age 2 because of breathing problems Proximal spinal muscular atrophy (SMA) is an autosomal recessive disease caused by a genetic defect in the SMN1 gene, which encodes SMN, a protein widely expressed in all eukaryotic cells.  Spinal muscular atrophy, or SMA, is an inherited condition that causes nerve cells in the lower part of the brain and spinal cord to break down and die. When this happens, the brain stops sending signals to the body's muscles. 1 Type III, also called Kugelberg-Welander disease or juvenile spinal muscular atrophy, begins to affect kids as early as 18 months of age or as late as adolescence. 2  This is the mildest form of SMA in children. 1 Type II, also called chronic infantile SMA, begins to affect children between 6 and 18 months old. 2  This form can be moderate to more severe. 3  Type III, also called Kugelberg-Welander disease or juvenile spinal muscular atrophy, begins to affect kids as early as 18 months of age or as late as adolescence. 1 Type III, also called Kugelberg-Welander disease or juvenile spinal muscular atrophy, begins to affect kids as early as 18 months of age or as late as adolescence. 2  This is the mildest form of SMA in children. Type II spinal muscular atrophy is characterized by muscle weakness that develops in children between ages 6 and 12 months. Children with type II can sit without support, although they may need help getting to a seated position. Individuals with this type of spinal muscular atrophy cannot stand or walk unaided. SMA-LED and the late-onset form of spinal muscular atrophy caused by VAPB gene mutations are inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Spinal muscular atrophy (SMA) is one of several hereditary diseases that progressively destroy lower motor neurons—nerve cells in the brain stem and spinal cord that control essential voluntary muscle activity such as speaking, walking, breathing, and swallowing. All three types are caused by defects in the SMN1 gene. 1  SMA type I, also called Werdnig-Hoffmann disease or infantile-onset SMA, is evident by the time a child is 6 months old. Here’s what you need to know about spinal muscular atrophy (SMA): 1  SMA is the number one genetic cause of infant mortality. 2  About 10 to 16 out of every 100,000 children are born with SMA. 1 SMA is the number one genetic cause of infant mortality. 2  About 10 to 16 out of every 100,000 children are born with SMA. 3  There are three types of SMA that vary greatly by age at onset and severity. 4  SMA type is determined by the highest motor function the child achieves. SMA (spinal muscular atrophy) is a disease that robs people of physical strength by affecting the motor nerve cells in the spinal cord, taking away the ability to walk, eat, or breathe. It is the number one genetic cause of death for infants. SMA is caused by a mutation in the survival motor neuron gene 1 (SMN1). In a healthy person, this gene produces a protein that is critical to the function of the nerves that control our muscles.
http://www.webmd.com/a-to-z-guides/spinal-muscular-atrophy https://en.wikipedia.org/wiki/Spinal_muscular_atrophy https://www.etch.com/kids-health/parents/spinal-muscular-atrophy-sma-90000/ https://www.etch.com/kids-health/parents/spinal-muscular-atrophy-sma-90000/ http://ghr.nlm.nih.gov/condition/spinal-muscular-atrophy http://www.ninds.nih.gov/disorders/sma/detail_sma.htm http://www.childrenshospital.org/conditions-and-treatments/conditions/spinal-muscular-atrophy-sma http://www.curesma.org/sma/about-sma/
how many babies born in us with spinal muscular atrophy