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Archive - Nov 22, 2013

Key Immunity Gene Discovered in Neanderthals

A research group at Bonn University in Germany and international collaborators have discovered a novel receptor, which allows the immune system of modern humans to recognize dangerous invaders, and subsequently elicits an immune response. The blueprint for this advantageous structure was also identified in the genome of Neanderthals, hinting at its origin. The receptor provided these early humans with immunity against local diseases. The presence of this receptor in Europeans but its absence in early men suggests that it was inherited from Neanderthals. The results have been published online on November 8, 2013 in the Journal of Biological Chemistry. When pathogens infect the human body, the immune system identifies and attacks dangerous invaders. During evolution, an efficient defense system developed, which vaguely resembles methods used by secret agents. With the help of certain genes, the human leukocyte antigen (HLA) system produces receptors that assess the risk rate of the pathogens using their profile which has just eight amino acids. "This function can be compared to a text which is identified by a spy as being suspicious, based on just a few letters of a word," says Professor Dr. Norbert Koch from the Institute for Genetics, Department of Immunobiology at the University of Bonn. In order to decipher this message, the immune system breaks down the invader’s proteins into peptides and subsequently scans a proportion of the peptides for their amino acid sequences. Up until now, a total of three different peptide receptors of more than 1000 different manifestations were known, which in humans can read the telltale letter combinations. "This variety is needed so that the immune system can rate the entire spectrum of pathogens relevant for humans," explains Professor Koch.

New Study Links Gene Variant to Marital Satisfaction

What makes some people more prone to wedded bliss or sorrow than others? Researchers at the University of California (UC) Berkeley and Northwestern University have found a major clue in our DNA. A gene involved in the regulation of serotonin can predict how much our emotions affect our relationships, according to a new study that may be the first to link genetics, emotions, and marital satisfaction. The study was conducted at UC Berkeley. “An enduring mystery is, what makes one spouse so attuned to the emotional climate in a marriage, and another so oblivious?” said UC Berkeley psychologist Dr. Robert W. Levenson, senior author of the study published online on October 7, 2013 in the journal Emotion. “With these new genetic findings, we now understand much more about what determines just how important emotions are for different people.” Specifically, researchers found a link between relationship fulfillment and a gene variant, or “allele,” known as 5-HTTLPR (serotonin-transporter-linked polymorphic region). Identified in the mid-1990s, 5-HTTLPR has been extensively investigated, particularly in connection with neuropsychiatric disorders. All humans inherit a copy of this gene variant from each parent. Study participants with two short 5-HTTLPR alleles were found to be most unhappy in their marriages when there was a lot of negative emotion, such as anger and contempt, and most happy when there was positive emotion, such as humor and affection. By contrast, those with one or two long alleles were far less bothered by the emotional tenor of their marriages. “We are always trying to understand the recipe for a good relationship, and emotion keeps coming up as an important ingredient,” said Dr.