Individuals with XXYY syndrome have 48 chromosomes. This chromosomal condition affects development in people assigned male at birth. XXYY syndrome is sometimes written as 48, XXYY syndrome or 48, XXYY. It occurs in an estimated one in every 18,000–40,000 male births.
While other primates like chimpanzees, gorillas, and orangutans also have 48 chromosomes, humans typically have 46 chromosomes. The difference in chromosome count between humans and these primates is due to a fusion event that occurred in the human lineage, resulting in the formation of human chromosome 2 from two ancestral chromosomes.
It's important to note that humans with 48 chromosomes do not become monkeys, as the extra chromosomes in XXYY syndrome are sex chromosomes, not autosomes.
