What is a tailless mouse called? - briefly
The condition is known as the tailless (tl) mutant mouse. It is a genetic variant that lacks a visible tail.
What is a tailless mouse called? - in detail
A mouse that lacks a visible tail is commonly referred to as a tailless mouse, often abbreviated as “tl mouse” in scientific literature. The designation originates from the genetic mutation named tl (short for “tailless”), which interrupts normal development of the vertebral column’s distal segments, resulting in an absent or severely reduced caudal appendage.
The tl allele is autosomal recessive; homozygous individuals display the characteristic absence of a tail, while heterozygotes retain a normal tail length. The mutation has been identified in several laboratory strains, most notably in the C57BL/6J background, where it is used to study developmental genetics, spinal cord formation, and the role of tail structures in locomotion and balance.
Key characteristics of the phenotype include:
- Complete lack of external tail tissue, often accompanied by a slight shortening of the sacral vertebrae.
- Normal forelimb and hindlimb function; gait alterations are minimal, allowing the animal to perform standard laboratory tasks.
- No impact on fertility, lifespan, or general health when maintained under controlled conditions.
Researchers employ tailless mice to explore gene‑environment interactions affecting axial skeletal development. The mutation provides a clear, observable marker for breeding programs and can be combined with other genetic modifications to assess compound phenotypes.
In the pet trade, the same term is used informally to describe domesticated mice that naturally lack a tail, though these are typically the result of the same tl mutation rather than a separate breed. The nomenclature remains consistent across scientific and hobbyist contexts, ensuring clear communication about the animal’s anatomical condition.