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A geneticist who investigates genetic contributions to variation in behavior. Comparisons among relatives and genomic measurements address population variation; a genetic association alone does not establish a single deterministic cause of an individual’s behavior.

Geneticist and first author of the original FOXP2 speech-and-language study. Lai and collaborators connected a mutation in a forkhead-domain gene with a severe inherited disorder, providing a molecular entry point into studying speech and language development.^[ref]

A scientist who studies heredity and variation. A geneticist may connect inherited traits with genes, measure how variants pass through families or populations, or alter a sequence experimentally to test its biological function.

Gerald M. Rubin is a geneticist whose contributions include genetic tools for Drosophila melanogaster. Primary institutional accounts connect his full name with the researcher credited as G. M. Rubin in the early gene-transfer work with Allan C. Spradling.^[ref][ref]

In their 1982 study, introduced DNA became integrated in germline chromosomes and was inherited. Restoration of a visible eye-color trait supplied one functional check; transfer of a segment without a recognizable visible effect showed that the method was not limited to that particular phenotype.^[ref]

The collaborators' 1983 vectors separated a scored genetic marker from other transferred DNA. A non-autonomous transposable element could carry inserted material while depending on a separate source of the machinery required for movement.^[ref]

An invented linkage example clarifies the marker's role. A transferred DNA segment contains both a visible marker and an experimental gene. Detecting the marker helps identify candidate carriers, but it does not by itself prove that the experimental gene is intact or has the intended expression. Conversely, lack of a visible effect from the experimental gene does not show that it failed to integrate. Presence, integrity and function require appropriately different evidence.

Rubin's contribution helped make these distinctions experimentally tractable: a biological trait could be investigated through the introduction and inheritance of specified DNA, with markers and molecular measurements supporting the interpretation.

Geneticist who analyzed the relationship between sex chromosomes and hybrid sterility. Haldane’s 1922 paper identified the recurring association of absent, rare or sterile hybrid offspring with the heterogametic sex.^[ref]

Geneticist and coauthor of the study identifying the mouse Clock gene through mutagenesis and mapping. The work connected an experimentally altered behavioral rhythm with a specific genetic locus.^[ref]

Geneticist who, with Esther Lederberg, developed replica plating to investigate bacterial mutants. Preserving the spatial pattern of colonies allowed selection to reveal variants that already existed before exposure.^[ref]

Geneticist whose experiments used yeast mutants to identify genes controlling the cell cycle. Isolating mutants that fail at particular stages makes the order and genetic requirements of cellular events experimentally accessible.^[ref]

Nevin D. Young is a geneticist whose research uses genomics to investigate communication between plants and microbes. His institutional profile emphasizes legumes, Medicago truncatula and the evolution of nitrogen fixation in association with bacteria.^[ref]

Young was first author of the 2011 draft Medicago truncatula genome report. The work combined sequence assembly with comparative genomics, including duplicated genomic regions and comparisons involving genes expressed strongly in root nodules. Such observations connect genome history with biological specialization, while a duplicated region by itself does not establish the function of every gene it contains.^[ref]

An original example illustrates why synteny can preserve evidence of whole-genome duplication despite later gene losses. Begin with four neighboring genes, A B C D. After duplication, suppose one descendant region retains A1 B1 D1, while the other retains A2 C2 D2. Both have lost a different gene, yet the retained A and D copies, their order and corresponding neighboring regions can still support a shared duplication history. Requiring two perfectly identical present-day gene lists would miss that relationship.

There is a second inference to keep separate. If B1 is strongly expressed in a root nodule, that observation concerns present gene expression; the duplicate arrangement concerns ancestry. Neither alone establishes that duplication caused a particular symbiotic function. Comparative sequence evidence and functional tests contribute different parts of that argument. A genome assembly supplies a framework in which those questions can be posed more precisely, rather than a complete explanation of how every gene operates.

Young's work thus illustrates the value of a well-chosen model plant: detailed genomic comparisons in Medicago truncatula can illuminate broader questions about legumes and plant–microbe relationships without making all species or all duplicated genes interchangeable.

Geneticist studying bacterial genome maintenance. Patricia Rosa coauthored research comparing maintenance functions of linear and circular plasmids in Borrelia burgdorferi, connecting unusual genome architecture with inheritance of extrachromosomal DNA.^[ref]

Geneticist studying the cell cycle. Paul Nurse and collaborators used fission-yeast mutants to identify genetic controls of division, establishing an experimental route from a cell-cycle phenotype to its molecular regulators.^[ref]

A geneticist who investigates inherited contributions to psychiatric traits and disorders. Family studies and genomic comparisons estimate patterns of liability and identify associated variants, whose effects depend on the population and measurement context.

Geneticist who, with Max Delbrück, used variation among bacterial cultures to investigate the origin of resistance to viruses. Their fluctuation experiment distinguished mutations arising before exposure from resistance induced only by the selecting agent.^[ref]

Geneticist and coauthor of the mouse Clock gene mapping study. The research used altered circadian behavior as a phenotype from which to identify a gene involved in biological timekeeping.^[ref]