Final answer:
Modern nonAfrican human genomes have approximately 1 to 4 percent Neanderthal DNA, with some populations showing up to 2.6 percent. The interbreeding occurred as early modern humans migrated out of Africa and encountered Neanderthals. This genetic inheritance has implications for health and disease in modern humans.
Step-by-step explanation:
Recent genetic analyses have revealed that modern nonAfrican human genomes contain approximately 1 to 4 percent Neanderthal DNA. This remarkable discovery came as a result of the sequencing of the Neanderthal genome and comparisons with present-day human genomes from various regions of the world. Moreover, some populations, such as those in East Asia, show genetic evidence accounting for about 2.3 to 2.6 percent of their DNA from Neanderthals. This interbreeding likely occurred as early modern humans migrated out of Africa and encountered Neanderthals inhabiting Europe and Asia.
The implications of this genetic inheritance are profound, suggesting that Neanderthals did not solely go extinct, but a part of them lives on in the genetic makeup of modern humans. Additionally, the presence of Neanderthal DNA has been linked to various health implications, such as certain immunities and susceptibilities to diseases.