( ( Tandem repeats ) ( ( ( occur ( in DNA ) ) ( when ( ( ( ( ( a pattern ) ( of ( ( ( one or ) more ) nucleotides ) ) ) ( is repeated ) ) and ) ( ( the repetitions ) ( are ( directly ( adjacent ( to ( each other ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Tandem) (NNS repeats)) (VP (VBP occur) (PP (IN in) (NP (NNP DNA))) (SBAR (WHADVP (WRB when)) (S (S (NP (NP (DT a) (NN pattern)) (PP (IN of) (NP (QP (CD one) (CC or) (JJR more)) (NNS nucleotides)))) (VP (VBZ is) (VP (VBN repeated)))) (CC and) (S (NP (DT the) (NNS repetitions)) (VP (VBP are) (ADJP (RB directly) (JJ adjacent) (PP (TO to) (NP (DT each) (JJ other))))))))) (. .)))
Tandem repeats occur in DNA when a pattern of one or more nucleotides is repeated and the repetitions are directly adjacent to each other.
(ROOT (S (ADVP (RB Deletions)) (VP (VB remove) (NP (NP (QP (CD one) (CC or) (JJR more)) (NNS nucleotides)) (PP (IN from) (NP (DT the) (NN dna)))))))