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General Information
Symbol
In(1)sc8
Species
D. melanogaster
Name
FlyBase ID
FBab0004197
Feature type
Also Known As
sc8
Computed Breakpoints include

1B2;h32

Sequence coordinates
X:382,384..382,384 (In(1)sc[8]:bk1)
X:21,368,973..23,542,271 (In(1)sc[8]:bk2)
Member of large scale dataset(s)
Nature of Aberration
Cytological Order
Progenitor
Mutagen
Class of aberration (relative to wild type)
Carries alleles
Transposon Insertions
Formalized genetic data

ac << bk1 << Zhr << bb << bk2

Genetic mapping information
Comments

The 5' (distal) end of this breakpoint corresponds to X:382 ,384 and the 3' (proximal) end corresponds to X:382 ,389 (release 6 coordinates). A 6-bp sequence (TTTCGT) from the ac-sc region is present at both breakpoint junctions, suggesting the inversion event created a small, staggered break at the euchromatic end. (FlyBase curator comment: coordinates updated from release 5 coordinates of X:276 ,417.. X:276 ,422 given in paper.)

This breakpoint is within the "1.688" satellite DNA repeat that covers approximately one-half of the X chromosome centric heterochromatin. A 6-bp sequence (TTTCGT) from the ac-sc region is present at both breakpoint junctions, suggesting the inversion event created a small, staggered break at the euchromatic end. (FlyBase curator comment: the coordinates used for this breakpoint correspond to the distal coordinate of the heterochromatin border defined in FlyBase (from FBrf0213099) through to the end of the sequenced chromosome.)

Left breakpoint between DNA coordinates 46.8 and 47.9 (Campuzano et al., 1985). 0 is an arbitrarily chosen EcoRI site in the scβ segment of ASC; positive values to the left (Carramolino, Ruiz-Gomez, Guererro, Campuzano and Modolell, 1982, EMBO J. 1: 1185-92).

Comments on Cytology

Left limit of break 1 from polytene analysis (FBrf0042024) Right limit of break 1 from complementation mapping against sc (FBrf0047940) Limits of break 2 from polytene analysis (FBrf0058564)

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
 
Phenotypic Data
In combination with other aberrations
NOT in combination with other aberrations

Mutants are viable and have normal bristle pigmentation.

Weak mutant for sc and shows a Hw effect. variegates for ac, y, and probably l(1)1Ac (Hess, 1962) in X0 male. Left break between ac and sc because induced deficiencies for the terminal uninverted portion of In(1)sc8 are deficient for y and ac but not sc8 (Patterson and Stone, 1935) and because In(1)sc8Lsc4R is deficient for sc (Sturtevant and Beadle, 1936); <up>i.e., for the α subdivision of the sc locus (Garcia-Bellido)</up>. Right break between bb and centromere because deficiencies for terminal genes are frequently deficient for bb (Patterson, 1933, Genetics 18: 32-52) as is In(1)sc4Lsc8R (Gershenson, 1933, J. Genet. 28: 297-313; Sturtevant and Beadle, 1936). In(1)sc8/+ female produces about 3% exceptional sons from 4-strand double crossing over within the inversion and about 8.7% recombination. In(1)sc8/+/Y female produces 19% secondary nondisjunction and 12% recombination (Sturtevant and Beadle, 1936; Grell, 1962, Genetics 47: 1737-54). In(1)sc8/0 partially male lethal (Baker, 1971; Johnson, Harger and Holm, 1979); variegates for y; ac enhanced.

Stocks (332)
Notes on Origin
Discoverer

Sidorov, 1929.

 
Balancer / Genotype Variants of the Aberration
 
Separable Components
 
Other Comments
 

"position-effect variegation for: l(1)1Ac" was stated as tentative.

Synonyms and Secondary IDs (3)
References (60)