Biological/Biochemical Features and Molecular Genetics of Specific Language Impairment (SLI)

Emrah Caylak, Karatekin University, Cankiri, Turkey

Published online: July 2011

DOI: 10.1002/9780470015902.a0023688

Common learning disorders include attention-deficit hyperactivity disorder, dyslexia, specific language impairment (SLI), speech–sound disorder and dyspraxia. They are influenced by genes and several research groups to attempt to identify susceptibility genes of learning disorders through the sequential analysis of genetic linkage and association. This review highlights the genetic contribution to SLI and the current molecular genetic researches aimed at identifying susceptibility and candidate genes for SLI. Currently, four susceptibility loci and three candidate genes (CMIP, ATP2C2 and CNTNAP2) associated with SLI have been found. This review also summarises the biological/biochemical features of SLI. The success of dietary intervention of nutritional supplements (i.e. thiamine and some fatty acids) to improve learning abilities in SLI and dyslexia suggests that a greater understanding of biochemical abnormalities may provide a useful addition with other treatment procedures for these learning disorders.

Key Concepts:

  • Learning disorders may cause the learner to receive and process some information inaccurately. People with learning disorders may have problems of basic psychological processes involved in understanding or in using language, spoken or written, that may manifest itself in an imperfect ability to listen, think, speak, read, write, spell or do mathematical calculations.
  • Individuals with specific language impairment (SLI) seem to have problems in pragmatics, such as discourse maintenance, use and range of speech acts and narrative abilities.
  • Genetic factors are important in specific language impairment.
  • Molecular genetic researches should be aimed to identify susceptibility genes for SLI.
  • Molecular advances in SLI will help to set the research agendas for future studies to follow.
  • The association and linkage studies of learning disorders may help us to understand the biological basis of normal learning variation, and shed light on more fundamental questions regarding the origin of human speech and language.

Keywords: learning disorders; specific language impairment; association; linkage; CMIP; ATP2C2; CNTNAP2

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Related Sub-Topics:

Molecular Genetics of Common and Complex Disease | Genetics of Intelligence and Cognition | Specific Genetic Disorders | Linkage Analysis
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Article Title: Biological/Biochemical Features and Molecular Genetics of Specific Language Impairment (SLI)
 
How to Cite close
Caylak, Emrah(Jul 2011) Biological/Biochemical Features and Molecular Genetics of Specific Language Impairment (SLI). In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0023688]