Genetic causes of intellectual disability in a birth cohort: A population‐based study

Abstract

Intellectual disability affects approximately 1–3% of the population and can be caused by genetic and environmental factors. Although many studies have investigated the etiology of intellectual disability in different populations, few studies have been performed in middle‐income countries. The present study estimated the prevalence of genetic causes related to intellectual disability in a cohort of children from a city in south Brazil who were followed from birth. Children who showed poor performance in development and intelligence tests at the ages of 2 and 4 were included. Out of 4,231 liveborns enrolled in the cohort, 214 children fulfilled the inclusion criteria. A diagnosis was established in approximately 90% of the children evaluated. Genetic causes were determined in 31 of the children and 19 cases remained unexplained even after extensive investigation. The overall prevalence of intellectual disability in this cohort due to genetic causes was 0.82%. Because this study was nested in a cohort, there were a large number of variables related to early childhood and the likelihood of information bias was minimized by collecting information with a short recall time. This study was not influenced by selection bias, allowing identification of intellectual disability and estimation of the prevalence of genetic causes in this population, thereby increasing the possibility of providing appropriate management and/or genetic counseling. © 2015 The Authors. American Journal of Medical Genetics Part A Published by Wiley Periodicals, Inc.

Correlates of burnout among professionals working with people with intellectual and developmental disabilities

“…Intellectual disability (ID) affects approximately 1-3% of the population (Karam et al 2015). It is estimated that about 2.5-4 million adults in the United States have an ID, and an even more have developmental disabilities (Lauer and McCallion 2015).…”

Genetics of Mental Retardation

“…В других работах по оценке генетического вклада в причины умственной отсталости получены в целом аналогичные показатели. Например, в недавнем ис-следовании определяли вклад генетических факто-ров в умственную отсталость у детей в возрасте от 2 до 4 лет [11]. Под наблюдением находился 4231 ре-бенок и 214 из них были включены в исследование.…”

“…Авторы отмечают, что умственная отсталость, вызванная генетическими причинами, в их исследо-вании составила 20,5%, что согласуется с данными других авторов о генетических причинах умственной отсталости (15-50%) [12][13][14][15][16]. Распространенность генетически обусловленной умственной отсталости в исследуемой когорте составила 0,82% по оценке авторов [11], т.е. 8,2 на 1000 новорожденных, общая распространенность умственной отсталости -3,56%.…”

Clinical utility of next-generation sequencing in neurodevelopmental disorders: non-syndromic intellectual disability as a model

“…[14] Genetic causes of ID are thought to be present in 15-50% of cases, [15][16][17][18][19][20] although this number increases proportionally with severity. [2,[21][22][23][24] Most severe forms of ID are due to chromosomal abnormalities or defects in specific genes.…”