( ( A ( dominant trait ) ) ( ( is ( ( the trait ) ( that ( ( will always ) ( be ( expressed ( if ( ( ( ( at least ) one ) ( dominant allele ) ) ( is present ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (JJ dominant) (NN trait)) (VP (VBZ is) (NP (NP (DT the) (NN trait)) (SBAR (WHNP (WDT that)) (S (VP (MD will) (ADVP (RB always)) (VP (VB be) (VP (VBN expressed) (SBAR (IN if) (S (NP (QP (IN at) (JJS least) (CD one)) (JJ dominant) (NN allele)) (VP (VBZ is) (ADJP (JJ present)))))))))))) (. .)))
A dominant trait is the trait that will always be expressed if at least one dominant allele is present.
(ROOT (S (NP (NP (DT An) (NN allele)) (SBAR (WHNP (WDT that)) (S (VP (VBZ 's) (ADVP (RB always)) (VP (VBN expressed) (PP (IN over) (NP (DT another)))))))) (VP (VBZ is) (NP (DT a) (JJ dominant) (NN allele))) (. .)))