A red male cardinal and a brownish female sit on a branch in front of a green background.
| 10+ min read
Animals across the tree of life have developed a mind-boggling variety of ways to become male or female.

Sex chromosomes

Artist’s rendition of two X chromosomes in blue, with a glowing orange line swirling around one.

Male and Female Stem Cells Derived from One Donor in Scientific First

Blue 3D illustration of X-shaped chromosomes

X Chromosome Silenced in Some Cancers in Males

Infographic: How Some X-Chromosome Genes Escape Inactivation

Genes that Escape Silencing on the Second X Chromosome May Drive Disease

Unbalanced Chromosomal Inheritance More Common than Thought

nettie stevens x and y chromosome name origin the scientist

How Chromosomes X and Y Got Their Names, 1891

Fruit Fly Geneticist Bruce Baker Dies

Why, Oh Y?

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Kirsty Wright is searching for evidence in a missing persons investigation. She is wearing a blue shirt and glasses. Behind her is dense vegetation and police procedural tape.

How a Forensic Biologist Exposed a DNA Lab Scandal That Shook Australia

Photo of John Calhoun crouches within his rodent utopia-turned-dystopia

Universe 25 Experiment

Hands holding an older woman’s hands.

One Gene Influences 75 Percent of Alzheimer’s Disease Cases

A picture of Rohita Roy, a postdoc at Stanford University.

Postdoc Portrait: Rohita Roy

Multimedia

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From Data to Discovery: Omics in Therapeutic Innovation

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Exploring Organoids for Disease Modeling Research

February 2026

A Stubborn Gene, a Failed Experiment, and a New Path

When experiments refuse to cooperate, you try again and again. For Rafael Najmanovich, the setbacks ultimately pushed him in a new direction.

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Human-Relevant In Vitro Models Enable Predictive Drug Discovery

Advancing Drug Discovery with Complex Human In Vitro Models

Stemcell Technologies
Redefining Immunology Through Advanced Technologies

Redefining Immunology Through Advanced Technologies

Ensuring Regulatory Compliance in AAV Manufacturing with Analytical Ultracentrifugation

Ensuring Regulatory Compliance in AAV Manufacturing with Analytical Ultracentrifugation

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Maximizing Cancer Research Model Systems

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Sino Biological Expands Research Reagent Portfolio to Support Global Nipah Virus Vaccine and Diagnostic Development

Beckman Coulter

Beckman Coulter Life Sciences Partners with Automata to Accelerate AI-Ready Laboratory Automation

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Refeyn named in the Sunday Times 100 Tech list of the UK’s fastest-growing technology companies