FB2026_03 , released September 17, 2026
CV Term Report
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Term cold sensitive amorphic allele - genetic evidence ID (Ontology) FBcv:0000740 (FlyBase CV)
Definition An allele inferred to completely lack function at low temperatures (restrictive temperatures) but not at high temperatures (permissive temperatures) from the observation that adding extra copies in the genome has no effect on the phenotype at the restrictive temperatures. Most commonly, evidence takes the form of the observation that the phenotype of homozygotes (2 copies) is identical to that seen when the allele is in trans to a deletion of the gene (1 copy).[ FlyBase:FBrf0002371 FlyBase:FBrf0049147 ]
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amorphic allele - genetic evidence
 |__temperature conditional amorphic allele - genetic evidence__
temperature conditional amorphic allele                         |
 |__temperature conditional amorphic allele - genetic evidence__|
 |__cold sensitive amorphic allele______________________________|
cold sensitive loss of function allele                          |
 |__cold sensitive amorphic allele______________________________|
                                                                cold sensitive amorphic allele - genetic evidence  1 rec.
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Is a temperature conditional amorphic allele - genetic evidence
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