What Are The Genetic Causes Of Mental Retardation?

What are the biological causes for mental retardation?

Biological risk factors for mental retardation include malnutrition; exposure to toxins such as lead, alcohol, and PCBs, and being born at LBW.

Social in¯ uences from homes, schools, and cultures are related to intelligence and mental retardation although the direction of effect is difficult to determine..

Is mental retardation curable?

A small study of 30 people with the most common inherited form of mental retardation has found encouraging evidence that some symptoms of the disorder can be alleviated with drugs.

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 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).

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.

What is the most common genetic cause of mental retardation?

X-linked mental retardation Fragile X syndrome is the most common inherited form of mental retardation and, after Down syndrome, the most common genetic form. It is X linked, with dominant inheritance, and the penetrance is lower in females.

Can mental retardation be genetic?

Mental retardation is caused by a number of different factors. Among genetic disorders, Fragile X syndrome and Down syndrome are the commonest causes of mental retardation. Fragile X syndrome (FXS) is an inherited form of mental retardation.

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.

What are the 4 levels of mental retardation?

The DSM-IV classifies mental retardation into four stages based on severity: mild (IQ score of 50-55 to approximately 70), moderate (IQ score of 30-35 to 50-55), severe (IQ score of 20-25 to 35-40), and profound (IQ score of less than 20-25).

At what age is mental retardation diagnosed?

When is the diagnosis made? The onset of mental retardation is in childhood, before 18 years of age. The diagnosis is generally made after infancy, between the preschool and school-age periods. Sometimes the diagnosis may be made later, at the time when a thorough assessment is performed.

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.

How do I know if my child has intellectual disability?

How Do I Know If My Child Has an Intellectual Disability?Sit up, crawl, or walk later than other children.Learn to talk later or have trouble speaking.Have trouble understanding social rules.Have trouble seeing the consequences of their actions.Have trouble solving problems.Have trouble thinking logically.

How do you test for intellectual disability?

Diagnosing Intellectual Disability Intellectual functioning is assessed with an exam by a doctor and through standardized testing. While a specific full-scale IQ test score is no longer required for diagnosis, standardized testing is used as part of diagnosing the condition.

What is the leading cause of mental retardation in newborns?

Fetal alcohol syndrome is now leading cause of mental retardation.

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.

What do they call mental retardation now?

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

How can you tell if a baby has mental retardation?

Signs may appear during infancy, or they may not be noticeable until a child reaches school age. It often depends on the severity of the disability. Some of the most common signs of intellectual disability are: Rolling over, sitting up, crawling, or walking late.

Does mental retardation get worse with age?

What mental changes occur, as adults with mental- retardation grow older? Like the general population after age 50, people with mental retardation, who do not have Down syndrome, experience a gradual decline in overall intellectual capacity, a decrease in their speed of recall, and slower general cognitive functioning.