Occasionally, the extra chromosome doesn't appear until early in the development of the embryo.

CNN: Triple X syndrome

It's also referred to as 47, XXX syndrome because of the existence of a 47th chromosome, which is the extra X chromosome.

CNN: Triple X syndrome

Because only some cells contain the extra X chromosome, females with the mosaic form of triple X syndrome may have less severe symptoms.

CNN: Triple X syndrome

He and his wife of 22 years, Claudia, have no children, and the cause became important to them after their niece was born with trisomy 13, a syndrome caused by an extra 13th chromosome.

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And that those who paid the same ticket price, bought the same game or applied for the same job should not have to expect to get harassed and insulted, or quizzed incessantly on their credentials, until any risk that they might have had fun is destroyed, simply because their extra X chromosome makes them instantly a cause for suspicion.

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