TBRS is characterised by increased growth (height, weight and/or head circumference) and an intellectual disability.
The increased length/height is evident from birth but individuals do not appear to gain excess weight until adolescence.
The associated intellectual disability is most commonly in the moderate range.
As children move into adolescence a recognisable facial gestalt becomes apparent characterised by a round face, heavy, horizontal eyebrows, narrow palpebral fissures and prominent central incisors.
Other clinical associations of TBRS include autistic spectrum disorder, kyphoscoliosis, joint laxity, hypotonia, cardiac anomalies and short widely spaced toes.