Resources by BioInteractive

DNA transcription (basic detail)

This animation shows that the first phase of the process of reading DNA information to make proteins starts with a molecule unzipping the DNA. The molecule then copies one of the strands of DNA into a strand of RNA, a close cousin of DNA. This process is called transcription.

This resource is part of the...

Evolution of the Y chromosome

How did the human Y chromosome become so small relative to its X counterpart? This animation depicts the 300-million-year odyssey of the sex chromosomes that began when the proto X and Y were an identical pair.

Human genome sequencing

The public Human Genome Project started by identifying unique marker sequences distributed throughout the genome. Then, many copies of a small section of DNA were randomly cleaved into smaller fragments, and each small fragment was sequenced. Because there were originally many copies of the DNA in question, many...

Human genomics: a guide for medicine

Dr. Lander explores human genetic variation and how it may affect individual susceptibility to certain diseases. With the exception of identical twins, no two human genomes are exactly the same. But how different are they? Are two humans more alike than two orangutans? Dr. Lander explores human genetic variation...

Mismatch repair

This animation illustrates how mistakes made during DNA replication are repaired. 

During DNA replication mistakes can occur as DNA polymerase copies the two strands. The wrong nucleotide can be incorporated into one of the strands causing a mismatch. Normally there should be an "A" opposite a "T" and "G"...

Paintbrush gene

In two related Drosophila species, a so-called paintbrush gene is activated to "paint" the pigment on the body. In one species, an extra switch activates the gene, resulting in spotted wings.

Paintbrush Gene Background...

Paired DNA strands

This animation illustrates the DNA double helix structure. If untwisted, DNA looks like two parallel strands. Each strand has a linear sequence of A, C, G, and T. The precise order of the letters carries the coded instructions. One strand is a complementary image of the other: A always pairs with T, and C always...

Polymerase chain reaction (PCR)

This video explains polymerase chain reaction.  PCR is a standard laboratory technique that allows amplification of specific segments of DNA based on complementarity.

Used with permission from...

Reading genes and genomes

Dr. Eric Lander takes us on a tour of this remarkable genetic century, describing the rapid advances in DNA sequencing technologies and information science. The 20th century opened with the rediscovery of Gregor Mendel's work on inheritance. By the close of the century, the human genome was almost fully sequenced....

Sanger method of DNA sequencing

Fred Sanger developed the first technique for sequencing DNA. DNA is replicated in the presence of chemically altered versions of the A, C, G, and T bases. These bases stop the replication process when they are incorporated into the growing strand of DNA, resulting in varying lengths of short DNA. These short DNA...