Scientists have shown that children born with Down syndrome have an additional, 47th chromosome (in healthy people, each cell has 46 chromosomes that carry important genetic information).
Ososayensi baye babonisa ukuthi abantwana abazalwa abane-Down syndrome, kukhona eyengeziwe, chromosome lika-47 (abantu enempilo, iseli ngalinye inama-chromosome angu-46, athwala ukwaziswa okubalulekile zofuzo).