( ( A linkage ) ( ( is ( ( a relationship ) ( between ( genes ( that ( tends ( to ( ( cause ( ( the characteristics ) ( of ( these genes ) ) ) ) ( to ( be ( inherited together ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT A) (NN linkage)) (VP (VBZ is) (NP (NP (DT a) (NN relationship)) (PP (IN between) (NP (NP (NNS genes)) (SBAR (WHNP (WDT that)) (S (VP (VBZ tends) (S (VP (TO to) (VP (VB cause) (NP (NP (DT the) (NNS characteristics)) (PP (IN of) (NP (DT these) (NNS genes)))) (S (VP (TO to) (VP (VB be) (VP (VBN inherited) (ADVP (RB together)))))))))))))))) (. .)))
A linkage is a relationship between genes that tends to cause the characteristics of these genes to be inherited together.
(ROOT (S (NP (JJ Certain) (NNS characteristics)) (VP (VBP are) (ADVP (RB frequently)) (VP (VBN inherited) (ADVP (RB together)) (PP (RB because) (IN of) (ADJP (JJ linkage))))) (. .)))