What makes us human?

Question 1

What are the two approaches that help in addressing these questions: how do humans differ from other species or subspecies and how do we differ among ourselves?

Answer 1

• Comparative genomics: for example, we can compare the human and chimpanzee genomes and ask how differences between these genomes might give rise to differences between these species
• Study of human mutations: many mutations alter phenotypes and give clues to the functions of the affected regions. Many mutations cause disease. The regions affected may encode structural proteins or enzymes or regulatory proteins or RNAs, or they may be DNA sequences that are targets of regulatory mechanisms. Understanding the effects of such mutations illuminates human biology and often has immediate clinical applications.

Question 2

What should we focus on to understand what makes us human or at least what makes us not chimpanzees

Answer 2

The human and chimpanzee genomes are about 96% identical. So, in order to understand what makes us human, we can focus on the around 13Mb of different sequences, rather than the full 3.2Gb. Humans and chimpanzees express very similar sets of proteins and most of the homologous proteins of chimpanzees and humans are identical or very similar. About 30% of homologous human and chimpanzee proteins show no differences at all. On average, there are only 2 amino acid differences.

Question 3

How do humans and chimpanzees develop differently

Answer 3

The answer lies within the static sequence of the genome. In 1975, scientists suggested that essential differences between