Word Pairs


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A new study shows that while [identically / identical] twins can look perfectly alike, it is not a perfect similarity. They are not [clozes / clones] of each other. Scientists at the University of Iceland analyzed the DNA from 387 pairs of identical twins - babies born from a single [sterilized / fertilized] egg. The scientists compared the DNA with [that / those] of the twins' parents and children. The geneticists looked for mutations in the [fast / early] stages of development. A [mutation / mutant] is a tiny change in the sequence of the DNA that can occur when a cell [shares / divides] . This change causes a [smite / slight] difference in the DNA replication process. A single, tiny change can create differences [in / on] height, intelligence, eye colour and even in [susceptibility / perceptibility] to disease.

The study shows that identical twins do not share [total / totally] identical DNA. In about 15 per cent of identical twin pairs, one twin carried a "[substantial / substantially]" number of mutations that the other did not share. The scientists say this [diffidence / difference] is important as it [shacks / sheds] light on the "nature versus [nurture / naturism]" debate. This is whether human behaviour is determined [of / by] the environment, socialization and upbringing, or by a person's [genes / jeans] . The research shows that this tiny difference, and not environmental [factors / factories] , could be the reason why [once / one] twin develops different behavioural characteristics or medical conditions. Professor Kari Stefansson said a genetic mutation may be the [source / sauce] of a given disease or trait.

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