Aneuploidy detection with a short-term hexaploid wheat assay

Area of Science:

• Genetics and Molecular Biology
• Plant Science
• Toxicology

Background:

• Aneuploidy, an abnormal chromosome number, is linked to various diseases and developmental issues.
• Existing methods for detecting aneuploidy-inducing agents can be complex, time-consuming, or require specialized equipment.
• There is a need for accessible and reliable assays to screen chemicals and physical agents for their potential to cause chromosomal aberrations.

Purpose of the Study:

• To describe and validate a new, cost-effective genetic assay for identifying agents that induce aneuploidy.
• To utilize allohexaploid wheat with specific genetic markers for the detection of chromosomal abnormalities.
• To assess the assay's reproducibility and applicability in identifying mutagenic factors.

Main Methods:

• Development of an assay using a specific wheat strain (Neatby's virescens) with a recessive allele (v1) affecting leaf pigmentation.
• Exploitation of chromosome 3B non-disjunction to generate detectable monosomic (green) and trisomic (cream-colored) sectors in leaves at low temperatures.
• Quantitative analysis of sector formation in successive leaves, correlated with shoot apex differentiation patterns, to measure genetic response to mutagens.

Main Results:

• The assay successfully detected aneuploidy induced by various agents, including X-rays, gamma-rays, p-fluorophenylalanine, caffeine, and vinblastine sulfate.
• Agents like diethylstilbestrol, sulfacetamide, safrole, and dichlorvos showed an increased tendency for sectoring.
• Cytological data from root tips corroborated the leaf sectoring observations, confirming the mechanism of aneuploidy induction.

Conclusions:

• The described wheat assay is a simple, fast, inexpensive, and reproducible method for detecting aneuploidy-inducing agents.
• The assay can quantify the genetic response to mutagenic factors and is suitable for use in multiple laboratories without extensive training.
• This assay serves as a valuable complement to existing tests for identifying chemicals and physical agents that cause non-disjunction and chromosomal aberrations.