Chromosomes of tuatara, Sphenodon, a chromosome heteromorphism and an archaic reptilian karyotype

Cytogenetic and Genome Research
T B NorrisCharles H Daugherty

Abstract

We examined karyotypes of the endemic New Zealand reptile genus Sphenodon (tuatara) from five populations, finding a karyotype unchanged for at least one million years. Animals karyotyped were from five geographically distinct populations, representing three groups, namely S. guntheri, S. punctatus (Cook Strait group), and S. punctatus (northeastern North Island group). All five populations have a diploid chromosome number of 2n = 36, consisting of 14 pairs of macrochromosomes and four pairs of microchromosomes. Chromosomal differences were not found between the five populations nor between female and male animals, except for one animal with a structural heteromorphism. Similarity between Sphenodon and Testudine karyotypes suggests an ancestral karyotype with a macrochromosome complement of 14 pairs and the ability to accumulate variable numbers of microchromosome pairs. Our research supports molecular phylogenies of the Reptilia.

Citations

Mar 18, 2006·Chromosome Research : an International Journal on the Molecular, Supramolecular and Evolutionary Aspects of Chromosome Biology·Shigehiro KurakuYoichi Matsuda
Mar 11, 2009·Proceedings of the National Academy of Sciences of the United States of America·Catherine PatratEdith Heard

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.