A Human Angle

/A Human Angle

Tracking Migration with Mitochondrial and Y-chromosome DNA

Wherever we go, we bring along traces of where we have been.  In genetic and genomic terms, this is the process of migration, the leaving of one population and the joining of another, either because of physical movements or because of changes in the reproductive structure of the population.  All parts of the genome can […]


Telomeres are the specialized structures at the ends of eukaryotic chromosomes.  Like many other fundamental properties of chromosomes, the existence of telomeres was first recognized by genetic experiments using Drosophila, performed by the “Fly Group” led by TH Morgan in the first decades of the 20th Century. The key experiments that recognized telomeres were done […]

The Sickle Cell Trait Heterozygote Advantage

According to eastern Nigerian mythology, an Ogbanje is a child who dies within a few months or years of birth and returns to a mythical land, only to re-enter the womb of his or her mother and be born again.  Chinua Achebe’s novel Things Fall Apart describes an ogbanje that was reborn nine times to […]

How Toadstools Affect Transcription

One of the most common and widespread mushrooms in Europe is also among the most toxic toadstools.  Amanita phalloides (familiarly known as the death cap mushroom or toadstool) grows throughout European forests, typically at the base of hardwood trees such as oaks, and is frequently encountered by picnickers and hikers in the late summer or […]

Exome Sequencing and Direct Searches for Causative Mutations

Genome-wide association studies (GWAS) currently dominate the research literature in human genetics, but they have some limitations.  Foremost among these is that, while a GWAS identifies regions of the genome associated with a trait or a genetic disease, it does not find the specific causative gene.  That is done by follow-up analysis; for many associations, […]

ABO Blood Types

Among genetic traits that we all share, the most familiar single gene trait in humans is probably our ABO blood type.  Other familiar shared heritable human traits, such eye color, are not controlled by a single gene.  Many traits that are inherited as a single gene are associated with genetic diseases, such as cystic fibrosis […]

Red-Green Colorblindness

Mutations that arise spontaneously usually occur as a result of unrepaired errors during replication, as discussed in Chapter 4, or as transposable element movement, as discussed in Chapter 3.  However, a few mutant alleles arise during recombination; the most familiar example is red-green colorblindness in humans.  The same process that produces red-green colorblindness has also […]

Analyzing the Black Death by Phylogenetics

Yersina pestis is a bacterial species that causes a deadly disease known as the Plague. Currently, outbreaks of the Plague occur in very few parts of the world, but ancient outbreaks had a major role in shaping human history. In the 14th century, a Plague outbreak referred to as the Black Death swept through Europe […]