Sentences with phrase «higher number of chromosomes»

Not exact matches

Using the correct numbers for the risk of miscarrying after an amniocentesis, the natural conclusion would seem to be that moms whose risk of having a baby with a chromosome disorder is less than 1 in 400 should not have an amniocentesis (since the odds of the test causing a miscarriage would be higher).

During periods of high stress, he says, men produce less testosterone, which can reduce the number and quality of the «male» sperm, which carry a Y sex chromosome.

Among its oddities: 52 chromosomes, including 10 sex chromosomes, as well as the highest number of repeated segments in the genome of any mammal sequenced so far.

Another reason that determining the genetic sequence of the Y chromosome is so difficult is that it is composed of an unusually high number of repeated sequences — regions where the sequence of As, Ts, Cs, and Gs are identical, or nearly identical, for thousands or millions of bases in a row.

The researchers then confirmed that the number of singly paired chromosomes — also called univalents — was higher in older mouse and even human egg cells, indicating that age - related segregation errors could be tracked back to increased numbers of prematurely separated chromosome pairs.

Venken first sought a vector that could handle large amounts of DNA efficiently, settling on a bacterial artificial chromosome, which was designed a couple years ago and is known to maintain only a few copies of the DNA (though it can produce a high number of copies if it is induced).

As the authors also observed in previous works, some aphids showed different chromosome numbers also comparing cells belonging to a same individual «forgetting» that chromosome instability within individuals should be typical of malignant cells and not of healthy insects showing a high reproductive rate.

Surveillance that is not stringent enough, on the other hand, would allow eggs with a lot of jumping gene - related errors to survive, and lead to a high level of birth defects, such as those caused by an incorrect number of chromosomes in the offspring.

A disproportionately high number of mendelian diseases are documented for the X chromosome.

Non-physiological alterations in chromosome number are well - established contributors to human disorders: they are responsible of a high percentage of miscarriages and a panel of diseases including Down syndrome, developmental disorders and cancer.

A. Bar heights indicate the degree to which each chromosome contains an unexpectedly high number of differentially methylated promoters.