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General Information
D. melanogaster
Compound (1) of Armentrout
FlyBase ID
Computed Breakpoints include
Sequence coordinates
Member of large scale dataset(s)
Nature of Aberration
Cytological Order

| 1A - 6F2 | 6F2 - 1A | 20 - 7A1 | 7A1 - 20 . |

Class of aberration (relative to wild type)
Class of aberration (relative to progenitor)
Causes alleles
Carries alleles
Transposon Insertions
Formalized genetic data
Genetic mapping information
Comments on Cytology

Ring shaped in mitotic metaphase.

Sequence Crossreferences
DNA sequence
Protein sequence
Gene Deletion and Duplication Data
Genes Deleted / Disrupted
Complementation Data
Completely deleted / disrupted
Partially deleted / disrupted
Molecular Data
Completely deleted
Partially deleted
Genes NOT Deleted / Disrupted
Complementation Data
Molecular Data
Genes Duplicated
Complementation Data
Completely duplicated
Partially duplicated
Molecular Data
Completely duplicated
Partially duplicated
Genes NOT Duplicated
Complementation Data
Molecular Data
Affected Genes Inferred by Location
    Phenotypic Data
    In combination with other aberrations
    NOT in combination with other aberrations

    An apparently completely stable, compound-ring-X chromosome; cannot produce single-X chromosome derivative by heterochromatic exchange.

    Stocks (19)
    Notes on Origin

    Armentrout, 1964.


    C(1)TR94 progenitor marked with y cv v sd . y sn g Apparently arose by a process describable as reversed crossing over in region 6F2 - 7A1. Current versions of this chromosome have apparently opened, since they are no longer ring-shaped in metaphase. Shown to have separated at 13E by Traverse and Pardue (1988, Proc. Nat. Acad. Sci. USA 85: 8116-20) such that the new order is 13E - 7A1 | 7A1 - 20.1 - 6F2 | 6F2 - 1 | 20 - 13E | 13E - 20.1 - 6F2 | 6F2 - 1 | 20 - 7A1 | 7A1 - 13E which are interconvertable by exchange between regions 20 and 13. The newly terminal ends at 13E have acquired moderately repeated sequences (He-T DNA) ordinarily encountered at telomeres and in the chromocenter (Traverse and Pardue). Transmission of C(1)A is reduced owing to the fact that half of meiotic exchanges lead to the production of dicentric chromosomes.

    Balancer / Genotype Variants of the Aberration
    Separable Components
    Other Comments

    The C(1)A chromosome has spontaneously opened in polytene region 13E to produce two new telomeres. Each of the new telomeres has acquired HeT-A DNA sequences.

    Should be the best of all compound-X chromosomes for stock purposes. Probably originally heterozygous for cv1, sn1, v1, g1, and sd1.

    Synonyms and Secondary IDs (2)
    Reported As
    Symbol Synonym
    Name Synonyms
    Compound (1) of Armentrout
    Secondary FlyBase IDs
      References (7)