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What is Mild MR – features are–a) Present in 5–10% populationb) ↑ Incidence in low socioeconomic groupc) Presents in 2 yearsd) Genetic background Present and explain in detail?
Mental retardation

Mental retardation (MR) refers to a group of disorders that have in common deficits of adaptive & intellectual function & an age of onset before maturity is reached.
According to statistics, 2.5% of the population should have MR, & 85% of these individuals should fall into the range of mild MR.

Presentation

MR presents by the age of the patient, i.e.

Newborn : Dysmorphism, major organ system dysfunction.
Early infancy (2-4 months) : Failure to interact with the environment, vision & hearing impairment.
Late infancy : Gross motor delay
Toddlers (2-3 yrs) : Language delays & difficulties.
School age (over 5 yrs) : Academic underachievement & behaviour difficulties.
Predisposing factors for mental retardation
i)    Low socio - economic strata              iii) Advanced maternal age           v) Genetically transmitted
Low birth weight                iv) Consanguinity