What Is The Common Type Of Chromosomal Abnormality Associated With Mental Retardation?

Is mental retardation a chromosomal disorder?

Chromosomal abnormalities are thought to be the most common cause of mental retardation (MR)..

What is the life expectancy of someone with mental retardation?

As the table shows, children or adults with profound, severe, or suspected retardation who were immobile, not toilet-trained, and tube-fed had a very low life expectancy and usually died within four years.

What is borderline mental retardation?

Borderline intellectual functioning, also called borderline mental retardation (in the ICD-8), is a categorization of intelligence wherein a person has below average cognitive ability (generally an IQ of 70–85), but the deficit is not as severe as intellectual disability (below 70).

What do they call mental retardation now?

The term “intellectual disability” is gradually replacing the term “mental retardation” nationwide.

What are the different causes of mental retardation?

What causes intellectual disability?trauma before birth, such as an infection or exposure to alcohol, drugs, or other toxins.trauma during birth, such as oxygen deprivation or premature delivery.inherited disorders, such as phenylketonuria (PKU) or Tay-Sachs disease.chromosome abnormalities, such as Down syndrome.More items…

What is the most common genetic cause of mental retardation?

Fragile X syndrome is the most common inherited form of mental retardation and, after Down syndrome, the most common genetic form.

What are the most common chromosomal disorders?

Some of the most common chromosomal abnormalities include:Down’s syndrome or trisomy 21.Edward’s syndrome or trisomy 18.Patau syndrome or trisomy 13.Cri du chat syndrome or 5p minus syndrome (partial deletion of short arm of chromosome 5)Wolf-Hirschhorn syndrome or deletion 4p syndrome.More items…

What are the types of mental retardation?

Mental retardation comprises five general categories: borderline, mild, moderate, severe and profound. Categories are based on scores obtained through use of age-standardized tests of cognitive ability (Table 1).

What is the most common level of mental retardation?

Most affected individuals have mild mental retardation (IQ of 50 to 70). Moderate mental retardation is defined by a tested IQ of between 35 to 40 and 50 to 55. Severe mental retardation is defined by a tested IQ of between 20 to 25 and 35 to 40.

Can mental retardation be reversed?

“The same mutation in animals produces learning disorders, which we were able to eliminate in adult mice. Our work and other recent studies suggest that some forms of mental retardation can be reversed, even in the adult brain.”

What are the signs and symptoms of chromosomal abnormalities?

Symptoms depend on the type of chromosomal anomaly, and can include the following:Abnormally-shaped head.Below average height.Cleft lip (openings in the lip or mouth)Infertility.Learning disabilities.Little to no body hair.Low birth weight.Mental and physical impairments.More items…

What causes mental retardation in a fetus?

Things that can interfere with fetal brain development include alcohol or drug use, malnutrition, certain infections, or preeclampsia. Problems during childbirth. Intellectual disability may result if a baby is deprived of oxygen during childbirth or born extremely premature.

Why does phenylketonuria cause mental retardation?

Mutations in the PAH gene can cause phenylketonuria (PKU), a disorder that can change cells in the brain. The faulty protein allows dangerously high levels of phenylalanine to accumulate in the brain, poisoning the cells. If a person with PKU consumes too much phenylalanine, the build-up can cause mental retardation.

What are some examples of chromosomal disorders?

Some chromosomal abnormalities occur when there is an extra chromosome, while others occur when a section of a chromosome is deleted or duplicated. Examples of chromosomal abnormalities include Down syndrome, Trisomy 18, Trisomy 13, Klinefelter syndrome, XYY syndrome, Turner syndrome and triple X syndrome.

Can you fix chromosomal abnormalities?

In many cases, there is no treatment or cure for chromosomal abnormalities. However, genetic counseling, occupational therapy, physical therapy and medicines may be recommended.

What are the four classifications of mental retardation?

The condition is further divided into four levels of retardation based on IQ, which include mild mental retardation (IQ between 50-55 and 70), moderate mental retardation (IQ between 35-40 and 50-55), severe mental retardation (IQ between 20-25 and 35-40), and profound mental retardation (IQ below 20 or 25) (American …

How do I know if I’m mentally challenged?

Rolling over, sitting up, crawling, or walking much later than developmentally appropriate. Difficulty communicating or socializing with others. Lower than average scores on IQ tests. Difficulties talking or talking late.

Does Klinefelter syndrome cause mental retardation?

Klinefelter syndrome (KS) has not typically been associated with mental retardation (MR), however, in recent years a growing body of evidence suggested that KS boys often experience language deficits and academic difficulties.