A frameshift mutation is a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read. A DNA sequence is a chain of many smaller molecules called ...

In the end, however, selection constantly sorts through the variation that is produced by mutations to select the fit and remove the unfit, while ignoring neutral changes. A few distinct types of ...

Applied since the 1930s to accelerate the process of developing and selecting new valuable agronomic traits, mutation breeding uses a plant’s own genetic make-up, mimicking the natural process of ...

To artificially induce hereditary changes in plants, either physical or chemical agents are used. Ionizing radiation is a widely used physical agent to treat the seeds and other plant material of ...

Researchers discovered that mammals - from tigers to humans - have roughly the same number of mutations by the time they die of old age. But short-lived animals tend to burn through their ...

However, changes in the genome do occur. These are known as mutations. Mutations can have two results: no protein is expressed an altered protein is expressed Some mutations can affect a few bases ...

How could a "bad" gene-- the mutation that causes the sometimes lethal sickle cell disease -- also be beneficial? On the other hand, if it didn't provide some survival advantage, why had the ...

Mutations occur continuously and can be spontaneous. Most are caused by errors when the DNA is copied prior to cell division. They can also happen because of: ionising radiation close ionising ...

Since the virus was first identified a year ago, thousands of mutations have arisen. The vast majority of mutations are "passengers" and will have little impact, says Dr Lucy van Dorp, an expert ...

The accumulation of mutations in DNA is often mentioned as an explanation for the aging process, but it remains just one hypothesis among many. A team from the University of Geneva (UNIGE), in ...

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PSEN1 encodes presenilin-1, a subunit of γ-secretase, the aspartyl protease responsible for Aβ generation. More than 300 mutations in PSEN1 have been reported and mutations in PSEN1 are the most ...