Doctors and scientists now have the ability to sequence a person’s DNA to look f

Doctors and scientists now have the ability to sequence a person’s DNA to look for abnormalities. One common example of genetic testing is screening for an extra chromosome 21 in human fetuses. This test is used to detect if a child will have Down’s Syndrome. Do some research and describe another example of genetic testing. What specifically do they look for in the DNA? How can genetic testing be beneficial and how far should we take it?  
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