The Genetic Legacy of Neanderthals in the Human Nose

• 22 May 2023

Why in News?

Recent research conducted by a team of scientists from the University College London and Fudan University, in collaboration with researchers worldwide, has shed light on the genetic factors influencing the human nose.

• The study identified genetic loci associated with the nose, including one locus influenced by Neanderthal ancestry.

What are the Key Highlights of the Reasearch?

• The Genetic Study:
  • The study analyzed 2D images and measured distances between facial landmarks in over 6,000 Latin American individuals.
  • The research identified 42 new genetic loci associated with the nose, with 26 of them being replicated in diverse populations including Asians, Europeans, and Africans.
    • A ‘locus’, plural ‘loci’, is the position of a particular gene on the human chromosome.
  • One specific locus, 1q32.3, previously linked to Neanderthal genetic contributions, was found to influence midface height.
    • The 1q32.3 locus contains the gene ATF3 (activating transcription factor 3), which is regulated by the forkhead box L2 (FOXL2) gene involved in skull and facial development.
• The Legacy of Neanderthals:
  • Genetic evidence suggests that Neanderthals and early humans interbred, leading to the introgression of Neanderthal genomic sequences into the human population.
  • The influential work of evolutionary geneticist Svante Pääbo, who won the Nobel Prize for Physiology and Medicine in 2022, has provided key insights into the interbreeding events between archaic hominids, such as Neanderthals and Denisovans, and modern humans.
    • This interbreeding has left lasting genetic imprints on our species, affecting various traits and disease susceptibilities.
    • Non-African populations today carry about 1-2% of Neanderthal DNA, highlighting the genetic legacy of this interbreeding event.
  • Apart from nose shape, Neanderthal genetic contributions have been implicated in the way humans respond to pathogens and their susceptibility to certain skin and blood conditions, cancers, and even depression.
  • The study highlights the growing body of evidence indicating the profound impact of Neanderthal and Denisovan genomes on modern human biology and health.

• The Future of Genomic Research:
  • The investigation of interbreeding events and their consequences represents an exciting frontier in genomic research.
  • As more studies contribute to our understanding of the interplay between archaic and modern human genomes, we will gain a more comprehensive picture of our genetic heritage.
  • This knowledge has the potential to revolutionize the study of diseases and enhance our appreciation for the intricate tapestry of human genetic diversity.

Who are Neanderthals?

• About:
  • Neanderthals lived in Eurasia from approximately 400,000 to 40,000 years ago.
  • They were a species of archaic humans closely related to modern humans, sharing a common ancestor.
• Physical Characteristics:
  • Neanderthals had a robust build and a stocky physique, adapted for survival in colder environments.
  • They possessed distinct physical features, including:
    • Prominent brow ridge.
    • Large nose.
    • Receding chin.
• Skills and Tools:
  • Neanderthals were skilled hunters and toolmakers.
  • They utilized stone tools and weapons for various purposes, reflecting their adaptability and resourcefulness.
• Cultural Sophistication:
  • Neanderthals had a sophisticated culture, as evidenced by:
    • Symbolic behavior, such as cave paintings and personal ornaments
    • Burial rituals, indicating an awareness of death and possibly spiritual beliefs.
    • Artistic expressions, showcasing their creativity and cognitive abilities.

Source: TH