Which genetic characteristic is associated with nondisjunction?

Nondisjunction refers to the failure of chromosome pairs to separate properly during meiosis, leading to gametes that have an abnormal number of chromosomes. This genetic characteristic results in conditions such as Down syndrome, where there is an extra copy of chromosome 21, known as trisomy 21.

Meiosis is the process that produces gametes (sperm and eggs) with half the normal number of chromosomes. During the first division of meiosis, homologous chromosomes should separate so that each gamete receives one chromosome from each pair. If nondisjunction occurs, it can result in gametes that contain either too many or too few chromosomes. When such a gamete participates in fertilization, it can lead to an embryo with a chromosomal abnormality.

The other options relate to different genetic processes and features but do not accurately describe nondisjunction. The transfer of alleles generally occurs during crossing over, not during chromosome separation. The inheritance of recessive traits involves alleles being passed down rather than a failure in chromosome separation, and mutations in mitochondrial DNA take place independently of the meiotic process and do not involve nondisjunction.