However multivalent pairing is common in many recently formed allopolyploids, so it is likely that the majority of meiotic stabilization occurs gradually through selection.Because pairing between homoeologous chromosomes is rare in established allopolyploids, they may benefit from fixed heterozygosity of homoeologous alleles. In certain cases, such heterozygosity can have beneficial heterotic effects, either in terms of fitness in natural contexts or desirable traits in agricultural contexts. This could partially explain the prevalence of allopolyploidy among crop species. Both bread wheat and Triticale are examples of an allopolyploids with six chromosome sets. Cotton, peanut, or quinoa are allotetraploids with multiple origins. In Brassicaceous crops, the Triangle of U describes the relationships between the three common diploid Brassicas (B. oleracea, B. rapa, and B. nigra) and three allotetraploids (B. napus, B. juncea, and B. carinata) derived from hybridization among the diploid species. A similar relationship exists between three diploid species of Tragopogon (T. dubius, T. pratensis, and T. porrifolius) and two allotetraploid species (T. mirus and T. miscellus). Complex patterns of allopolyploid evolution have also been observed in animals, as in the frog genus Xenopus. Aneuploid
Organisms in which a particular chromosome, or chromosome segment, is under- or over-represented are said to be aneuploid (from the Greek words meaning "not", "good", and "fold"). Aneuploidy refers to a numerical change in part of the chromosome set, whereas polyploidy refers to a numerical change in the whole set of chromosomes. Endopolyploidy
Polyploidy occurs in some tissues of animals that are otherwise diploid, such as human muscle tissues. This is known as endopolyploidy.
Lymphocytic meningoradiculitis, also known as Bannwarth syndrome, is a neurological disease characterized as intense nerve pain radiating from the spine. The disease is caused by an infection of Borrelia burgdorferi, a tick-borne spirochete bacterium also responsible for causing Lyme disease. Signs and symptoms
Lymphocytic meningoradiculitis is characterized by an intense spinal pain in the lumbar and cervical regions, radiating to the extremities. Symptoms may include facial paralysis, abducens palsy, anorexia, tiredness, headache, double vision, paraesthesia, and erythema migrans. Treatment
Lymphocytic meningoradiculitis is treated with antibiotics. Oral doxycycline or IV ceftriaxone are typically recommended for 14-21 days. History
The disease was first reported in 1941 by German neurologist, Alfred Bannwarth, who described the main symptoms as intense radicular pain, facial palsy, severe headaches, and vomiting. A common feature he observed in his infected patients was an abnormal increase of lymphocytes in their cerebrospinal fluid (CSF). See also
Tick-borne disease

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