A plasmid is a circular, independent, nonchromosomal
strand of DNA found in some bacteria.
Researchers at the University of British Columbia in Vancouver have completed what they call the first rigorous analysis of whether nonchromosomal
birth defects increase with maternal age.
Four regions of Cohort 9,085 cases with 2010 England, chromosomal and 1991-1999; nonchromosomal
759,993 births anomalies, live births and fetal deaths [greater than or equal to] 20 weeks; all live and stillbirths Marshall et al.
Rather, it's an indication for evaluation of nonchromosomal
factors associated with recurrent miscarriage," she said.
The 23 chromosomes in a sperm are more tightly packed than are the 23 in an egg, and eggs contain more nonchromosomal
ingredients than do sperm.