I have a cat and her name is Kubla. She is part of the feline sister duo otherwise known as Kubla & Khan, and one of the cat quartet living in my house. Over the years, my husband and I have noticed that there’s something a little off about her. She lacks all of the characteristics particular to her species and necessary for survival.
We’re on constant Kubla patrol as she’s always in a state of potential danger. She has no sense of balance, self-preservation, self-defense or any awareness of her surroundings, other than the constant threat of plastic bags. Had she been an outside cat, she very likely wouldn’t have made it; there are no hunter or survivor instincts to speak of. Approaching fire rather than avoiding it, she regularly burns her whiskers off by trying to hug a boiling kettle. She spends a half hour in the litter box each time, for no particular reason, and yes, she knows how to get out.
She also exhibits peculiar social behavior in regards to our other cats. For example, while she is the frailest of them all, she reigns supreme as conflict instigator. Displaying unprovoked aggression, she either swaps at the others, growling and almost always missing, or quickly submits to them if she’s being attacked. She also seems to be completely unaffected by any sort of conditioning; feeding or sleeping patterns are entirely forgotten each night. Khan, her sister and littermate, demonstrates no abnormal social or cognitive behavior.
Kubla got me thinking about intellectual disability (ID). Once referred to as mental retardation, ID is characterized by below-average intelligence or mental ability, and a lack of skills necessary for day-to-day living. Turns out that approximately 2-3% of all children are born with some type of it, and for a long time, genetic conditions were thought to be its leading causes. Any alterations in the genetically encoded information that critically influences brain development can cause serious consequences on mental processes.
In 2006, a new study showed that the majority of the single genes associated with intellectual disability have lots to do with the X chromosome, confirming that genetics do in-fact play a vital role, but they are not the only factors. However, in 2008, UCLA researches discovered that an FDA-approved drug reverses the brain dysfunction inflicted by a genetic disease called tuberous sclerosis complex (TSC).
Three days after the administration of a drug called rapamycin, symptom reversal in lab mice was observed. “Our research shows that the disease’s learning problems are caused by reversible changes in brain function – not by permanent damage to the developing brain” stated the team.
This groundbreaking finding suggests that intellectual disability is not only a product of abnormal brain development, but also that there are other factors involved as well. As more and more research is underway, I have to wonder why littermates, such as Kubla and Khan, can be so different. If intellectual disability is not so strictly genetic, can Kubla change? And if so, how? –Liz Belilovskaya