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Mental retardation causes

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Chelsea Mae Nobleza, M.D.[2]

Overview

Overview

Possible causes for intellectual disability can be divided into genetic causes and environmental factors.

Causes

Causes

In less than 50% of individuals with mild ID, a specific cause is identified, and it increases to 75% in those with severe ID. [1]

Genetics

Down syndrome (Trisomy 21) is the most common genetic cause of ID, while Fragile X is the most common inherited cause of ID. [1]

Environmental Factors

Alcohol exposure during pregnancy, lead and other heavy metals, iodine deficiency, brain infections, congenital rubella syndrome, and cytomegalovirus infections, as well as hypoxic-ischemic injury, and periventricular hemorrhages all cause brain injury resulting in disability. [2]

References

References

  1. 1.0 1.1 Moeschler, J. B.; Shevell, M. (2014). “Comprehensive Evaluation of the Child With Intellectual Disability or Global Developmental Delays”. PEDIATRICS. 134 (3): e903–e918. doi:10.1542/peds.2014-1839. ISSN 0031-4005.
  2. “Intellectual Disability and Mental Health Problems : Evaluation of Two Clinical Assessment Instruments, Occurrence of Mental Health Problems and Psychiatric Care Utilisation”.

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