( ( In ( other words ) ) ( , ( ( ( ( ( ( the ( dominant allele ) ) ( is expressed ) ) , ) and ) ( ( the ( recessive allele ) ) ( is not ) ) ) . ) ) )
(ROOT (S (PP (IN In) (NP (JJ other) (NNS words))) (, ,) (S (NP (DT the) (JJ dominant) (NN allele)) (VP (VBZ is) (VP (VBN expressed)))) (, ,) (CC and) (S (NP (DT the) (JJ recessive) (NN allele)) (VP (VBZ is) (RB not))) (. .)))
In other words, the dominant allele is expressed, and the recessive allele is not.
(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))) (. .)))