Uso del índice digital D2:D4 como indicador biológico del trastorno específico del lenguaje

espanolIntroduccion Encontrar marcadores biologicos del trastorno especifico del lenguaje facilitaria su deteccion e intervencion precoz. En este sentido, el indice digital D2:D4 es considerado un indicador indirecto de la exposicion prenatal a la testosterona, y estudios previos lo han relacionado con la competencia linguistica y la conducta agresiva, por lo que podria ser un candidato a marcador biologico. El objetivo es comparar el valor de este indice digital en ninos con trastorno especifico del lenguaje (TEL) frente a sujetos con desarrollo tipico del lenguaje, estableciendo en que medida correlacionan los valores del indice biologico con la conducta (linguistica, cognitiva, social…) de dichos sujetos. Sujetos y metodos Se comparo el indice D2:D4, el lenguaje, la cognicion y la conducta social en un grupo de ninos con TEL (n=15) con un grupo de ninos sin dificultades del lenguaje (n=16) de la misma la misma edad (entre 5-8 anos), sexo (masculino) y nivel sociocultural. Resultados Los ninos con TEL mostraron valores significativamente mas altos en el indice D2:D4 de la mano derecha, y una correlacion negativa entre el indice D2:D4 de la mano derecha y la competencia linguistica. Aunque los ninos con TEL mostraron peores habilidades adaptativas y conductas internalizantes, aunque no mayor agresividad, estas medidas no se correlacionaron con el indice D2:D4, y si con los valores de lenguaje y de cognicion. Conclusiones Un valor mas alto del indice biologico D2:D4 (menor exposicion intrauterina a la testosterona) parece estar asociado con las dificultades del lenguaje de los ninos con TEL, pero no con sus dificultades conductuales. Las dificultades conductuales de estos ninos parecen ser consecuencia de sus dificultades linguisticas y de su nivel de cognicion. EnglishIntroduction The finding of biological markers of specific language impairment would facilitate their detection and early intervention. In this sense, the 2D:4D finger ratio is considered an indirect indicator of prenatal exposure to testosterone. Previous studies have related it to linguistic competence and aggressive behaviour, and could be a candidate for a biological marker of language impairment. The aim was to compare the value of the 2D:4D ratio in children with Specific Language Impairment (SLI) with those of children with typical language development, as well as to establish to what extent this biological index correlates with the behaviour (linguistic, cognitive, social,...) in both groups. Subjects and methods 2D:4D ratio, language, cognition and social behaviour were compared in a group of children with SLI (n=15), with a group of children without language difficulties (n=16) of the same age (between 5-8 years), gender (male), and socio-cultural level. Results Children with SLI showed significantly higher values of 2D:4D ratio of the right hand, and a negative correlation between this ratio and their linguistic competence. Although the children with SLI showed impaired adaptive abilities, but not more aggressive behaviour, these measurements did not correlate with the 2D:4D index. Nevertheless, social behaviour correlated with language and cognition competence. Conclusions A higher value of the biological 2D:4D ration (lower intrauterine exposure to testosterone) seems to be associated with language difficulties in boys with SLI, but not with their behavioural difficulties. Their behavioural difficulties seem to be a consequence of their linguistic difficulties and their level of cognition.