Comment Comment by Retric All species that sexually reproduce occasionally have the wrong number of chromosomes show up in an offspring. In humans it occurs in ~0.6% of live births. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3681172/Down syndrome is an example of that anomaly rather than some mutation that’s passed down. It’s an extra partial or complete copy of chromosome 21, and therefore can happen to any couple. parent Retric 2 years ago
Down syndrome is an example of that anomaly rather than some mutation that’s passed down. It’s an extra partial or complete copy of chromosome 21, and therefore can happen to any couple.