FB2026_02 , released June 18, 2026
Aberration: Dmel\In(1)AB
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General Information
Symbol
In(1)AB
Species
D. melanogaster
Name
FlyBase ID
FBab0003876
Feature type
chromosomal_inversion
Computed Breakpoints include

9E7-9E8;13E1-13E2

Sequence coordinates
X:10,778,576..10,778,576 [-] (In(1)AB:bk1)
(Zhang et al., 1999)
Member of large scale dataset(s)
Nature of Aberration
Cytological Order
Progenitor
Mutagen
Class of aberration (relative to wild type)
chromosomal_inversion
(FlyBase, 2007)
Class of aberration (relative to progenitor)
chromosomal_inversion
(Davis et al., 1996, Hutter and Karch, 1994, Koryakov et al., 1994, Zhimulev, 1994, Hutter et al., 1990)
Breakpoints

9E1-9E4;13E1-13E4

(Hutter et al., 1990)

10B;13F

(Koryakov et al., 1994)

9E7-9E8;13E1-13E2

(Zhimulev, 1994)

9E6;12C

(Hutter and Karch, 1994)

9E;13E

(Davis et al., 1996)
Causes alleles
Carries alleles
Hmr2
(Aruna et al., 2009)
Transposon Insertions
Formalized genetic data

bk1 << sesB << bk2 << sd

Genetic mapping information
Comments

The distal breakpoint of In(1)AB lies 406 base pairs before the 3' end of the four annotated transcripts from the CG15211 gene.

(Hutter, 2009.10.19)

Hmr maps distal to the distal In(1)AB breakpoint.

(Zhang et al., 1999)

Breakpoint mapped to an intron in sesB.

(Hutter and Karch, 1994)
Comments on Cytology

Limits of break 1 from polytene analysis (FBrf0074902) Left limit of break 2 from polytene analysis (FBrf0051988) Right limit of break 2 from polytene analysis (FBrf0074902)

Sequence Crossreferences
DDBJ / EMBL / GenBank
DNA sequence
Protein sequence
AJ236835
Gene Deletion and Duplication Data
Genes Deleted / Disrupted
Complementation Data
Completely deleted / disrupted
Hmr
(Hutter and Karch, 1994)
Partially deleted / disrupted
Molecular Data
Completely deleted
Partially deleted
CG15211
(Hutter, 2009.10.19)
Genes NOT Deleted / Disrupted
Complementation Data
 
Hmr
(Zhang et al., 1997)
sesB
(Zhang et al., 1997)
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 (0)
    If no genes are listed here, it may be because the affected region is very large. The JBrowse insert above may show an error for the same reason, and other FlyBase tools such as CytoSearch may also fail for large regions. You can contact FlyBase for more help.
    In these cases, there will be no "Export to Hitlist" button to the left.
    Phenotypic Data
    In combination with other aberrations
    NOT in combination with other aberrations

    Homozygous viable.

    (Zhimulev, 1994)

    FlyBase curator comment: It has been shown that the hybrid rescue associated with the In(1)AB chromosome is due to a lesion on the chromosome that affects Hmr function (Hmr2) and which is not associated with either inversion breakpoint (see FBrf0207733). Thus all information regarding hybrid rescue that had previously been reported in the literature for In(1)AB has been moved in FlyBase from the In(1)AB aberration report to the Hmr2 allele report.

    (FlyBase, 1992-)

    Primary nondisjunction 0.5%, secondary 29.3%; recombination 18.2% in In(1)AB/+ and 26.3% in In(1)AB/+/Y female (Grell, 1962, Genetics 47: 1737-54). Stone and Thomas (1935) obtained 14.3% recombination in In(1)AB/+.

    Stocks (3)
    Notes on Origin
    Discoverer

    Bodeman.

     

    The In(1)AB chromosome carries a lesion in Hmr (Hmr2), which is responsible for the hybrid rescue associated with the chromosome.

    (Aruna et al., 2009)
    Balancer / Genotype Variants of the Aberration
     
    Separable Components
     
    Other Comments
     

    FBrf0051988 reported that the In(1)AB chromosome (which carries the Hmr2 allele) can prevent the larval lethality of hybrid males from crosses between D.simulans males and D.melanogaster females and the embryonic lethality of hybrid females from the reciprocal cross. A known Zhr[+] allele was recombined onto the In(1)AB chromosome, and the resulting chromosome can only prevent the hybrid male larval lethality, thus the two rescuing actions reported for the In(1)AB chromosome are not due to a single gene.

    (Sawamura et al., 1993)

    FlyBase curator comment: It has been shown that the hybrid rescue associated with the In(1)AB chromosome is due to a lesion on the chromosome that affects Hmr function (Hmr2) and which is not associated with either inversion breakpoint (see FBrf0207733). Thus all information regarding hybrid rescue that had previously been reported in the literature for In(1)AB has been moved in FlyBase from the In(1)AB aberration report to the Hmr2 allele report.

    (FlyBase, 1992-)
    Synonyms and Secondary IDs (1)
    References (34)