BIRDS FOR PRODUCING FEMALE HATCHLING AND METHODS OF PRODUCING SAME

Smart overview of the Invention

The patent outlines methods and compositions for creating genetically modified female birds that, when mated with native male birds, exclusively produce female offspring. This innovation aims to address the significant issue of sex separation in commercial avian breeding, particularly for chickens, where culling of male chicks is a common practice due to their lack of utility in egg production and meat efficiency.

Background

In the poultry industry, managing sex ratios is crucial for optimizing production. Currently, billions of male chicks are culled annually, leading to ethical and economic concerns. The natural mechanism of sex determination in birds relies on the Z-W chromosome system, where females have a Z-W chromosome pair and males have a Z-Z pair. The divergence of the chicken W chromosome from human Y chromosomes complicates the understanding and manipulation of sex-specific traits in avian species.

Key Discoveries

The invention is based on the unexpected finding that editing one or more Z-chromosome gametologs can result in a genetic framework where only female offspring are viable from the modified females. The modified Z chromosome in females prevents the development of male embryos, while males can still produce viable gametes due to their non-modified Z chromosome compensating during fertilization.

Methodology

The methods described involve one-step site-directed mutagenesis techniques that minimize potential genetic disruptions. The resulting genetically modified birds are considered non-transgenic, thereby addressing regulatory and public concerns regarding genetically modified organisms (GMOs). These methods also allow for the production of male birds that can generate female-biased hatchling populations without necessitating the destruction of embryos or chicks.

Applications and Benefits

• Reduction of culling practices in poultry farming.
• Enhanced management of breeding flocks by ensuring a higher ratio of female hatchlings.
• Utilization of non-transgenic methods to align with consumer preferences and regulatory standards.
• Potential applications extend beyond chickens to other avian species such as quail, turkeys, and ducks.