Are you generous people? It's probably written in your genes

This is according to the results of a new study by Dr. Ariel Knafo and a team of researchers from the Department of Psychology at the Hebrew University

Are people who tend to be generous genetically programmed for it? Dr. Ariel Knafo and a team of researchers from the Department of Psychology at the Hebrew University believe that the answer to this is definitely yes.
The team of researchers examined this question through an experiment in the form of an online game in which the researched are required to decide whether to share their money with other participants. The researchers found that subjects who chose to give their money to others differed genetically from participants who chose to keep their money in their hands.
The experiment involved 203 subjects who played against another anonymous player "online". Each player could decide whether to keep the NIS 50 initially given to him, or to give a part of it, or even the entire amount, to another player, who could not return the favor.
In the next phase of the experiment, DNA samples were taken from the subjects, which were decoded and compared to their responses as recorded during the experiment. It was found that those whose genetic material contains a certain variant (version) of a gene called AVPR1a tended to share their money with others about 50 percent more (on average) than players whose DNA contains another variant of the same gene. The results of the study were recently published in the online edition of the research journal "Genes, Brain and Behavior", and will soon be published in the printed version of the journal.
"The experiment provided the first evidence, to the best of my understanding, of a link between DNA differences and true human altruism," said Dr. Kanaf, who conducted the study together with Prof. Richard Ebstein, Prof. Gary Bornstein and research student Shlomo Israel from the department for psychology at the Hebrew University.
The AVPR1a gene codes for the production of a receptor that allows the vasopressin hormone to act on brain cells. This hormone is involved in the processes of creating social relationships. The researchers found a greater tendency to altruism among subjects in whom the segment in the AVPR1a gene, called the "promoter site", was longer. The promoter site is the part of the gene that allows the cellular machinery to unite with it and determine what amount of hereditary material will actually be produced. In the case of the AVPR1a gene, a long promoter site may result in increased activity of the gene.
"The findings could help biologists to investigate and understand the historical development of altruism," the scientists claim. They also add that: "A certain version of the AVPR1a gene is also present in rodents of the Nevarni type, and in them this gene is also responsible for promoting social relationships. This fact raises the possibility that altruism has deep roots in the genetic history of living beings, which are expressed in the differences between humans."