Spinal Muscular Atrophy

Spinal Muscular Atrophy (SMA): Spinal Muscular Atrophy affects the neurons in the cat’s spine, resulting in an awkward gait and odd posture. The affliction is not fatal and relatively not painful in Maine Coons. SMA is due to a recessive gene; if a Maine Coon kitten receives this gene from both parents, it will start showing signs of the disease within 3 to 4 months after birth. Kittens who receive the gene from one parent will not acquire SMA. Signs and symptoms include:

• Loss of muscle mass in hindquarters (cat may sway as it walks)
• Posture will appear abnormal
• Cat will struggle to jump
• Progressive muscular instability and weakness
• Fine muscular tremors and fasciculations (muscle contractions)

There is, unfortunately, no way to slow or stop the progression of SMA. However, your cat can still live a long and healthy life with proper care. Cats with SMA should be kept indoors, as they cannot get out of harm’s way as quickly as a cat with no spinal abnormalities. Owners also need to take care to keep all of their cat’s food, water and other necessities on the same level. If your cat has a favorite perch, you can add a small set of stairs or a few stools to minimize jumping.

We feel it is unethical to breed kittens that will product a positive result for muscular atrophy affected kittens. We genetically test Spinal Muscular Atrophy with UC Davis.

Per CU Davis, DNA testing is done via a mouth swab.

Spinal Muscular Atrophy (SMA) in Maine Coon Cats

Quick Summary

Spinal muscular atrophy (SMA) is characterized by progressive instability with unsteady gain and posture abnormalities due to loss of motor neurons in the lower spinal and atrophy of muscles in the hind limbs.

Phenotype:  Spinal muscular atrophy (SMA) is characterized by progressive instability with unsteady gain and posture abnormalities due to loss of motor neurons in the lower spinal and atrophy of muscles in the hind limbs. Affected kittens first show signs of SMA at about 3-4 months of age.

Mode of Inheritance:  Autosomal recessive

Alleles: N = Normal/Unaffected, S = Spinal muscular atrophy

Explanation of Results:

Cats with N/N geontype will not have spinal muscular atrophy.  They cannot transmit this spinal muscular atrophy variant to their offspring.

Cats with N/S genotype will not have spinal muscular atrophy, but are carriers. They will transmit this spinal muscular atrophy variant to 50% of their offspring. Mating between two carriers are predicted to produce 25% spinal muscular atrophy kittens.

Cats with S/S genotype will have spinal muscular atrophy, a non-fatal but disabling condition.