VIDEO: Open with over-shoulder shot of CWRU genetic researcher comparing genes on computer screen. Cut to sequence of related shots.

Cut to shot of lead researcher, Joseph Nadeau.

Shot of magazine cover, Nature Genetics. Cut to shot of genes on computer screen.

VOICEOVER: MEDICAL RESEARCHERS ARE CLOSER THAN EVER TO FINDING THE GENES RESPONSIBLE FOR SUSCEPTIBILITY TO TESTICULAR CANCER, THE MOST COMMON CANCER AFFECTING YOUNG MEN. AT CASE WESTERN RESERVE UNIVERSITY IN CLEVELAND, PROFESSOR JOSEPH NADEAU HAS NARROWED THE SEARCH TO A SINGLE CHROMOSOME. HIS FINDINGS WERE RECENTLY PUBLISHED IN THE JOURNAL NATURE GENETICS. NADEAU SAYS FINDING THE GENES RESPONSIBLE FOR SUSCEPTIBILITY COULD ALSO HELP EXPLAIN WHY THE DISEASE RESPONDS SO WELL TO TREATMENT.

SOT & SUGGESTED SUPER: Joseph Nadeau, CWRU professor of genetics.

Cut to shot of genes on computer screen. Cut back to on-screen interview.

Pan of graphic illustration of a chromosome.

Cut to shot of Nadeau handling genetically bred 129/Sv mice in lab. Cut to lab assistant pouring liquid. Cut to mouse in hand.

ON-CAMERA INTERVIEW: Joseph Nadeau, CWRU professor of genetics

INTERVIEW: No one understands why testicular cancer responds so well to treatment. Some of the treatment protocols for testicular cancer are also used for other kinds of cancers, but they're far less effective. The hope is that by finding some of the genes that are involved in controlling susceptibility to testicular cancer, we'll get a better sense of the underlying genetics and biology, the bigger picture. (TRT = 0:26)

VIDEO: Researcher checks genes on computer screen.

VOICEOVER: THE KEY TO FINDING THESE ELUSIVE SUSCEPTIBILITY GENES IS ELIMINATING THE CLUTTER OF COMPLEX TRAITS THAT ARE NATURALLY PRESENT IN HUMAN CHROMOSOMES. NADEAU ACCOMPLISHED THIS BY BREEDING A PURE STRAIN OF MICE EXCLUSIVELY SUSCEPTIBLE TO THE CANCER, AND DEVELOPED A PROCESS CALLED CHROMOSOME SUBSTITUTION.

Cut back to Nadeau interview.

INTERVIEW: These chromosome substitution strains simultaneously tell you where the gene is and give you a mouse that you can use for subsequent research to look at the genetics and biology of the trait. Now we know that there's a gene on the chromosome, now we have a resource to use for fine mapping, and now the search is on to identify the gene on that chromosome. (TRT = 0:23)

VIDEO: Lab researcher piping genetic samples. Cut to 1st researcher at computer.

Cut to black.

VOICEOVER: CHROMOSOME SUBSTITUTION WILL ADVANCE THE TREATMENT OF TESTICULAR CANCER AND GO A LONG WAY IN SIMPLIFYING GENETIC ANALYSIS OF ALL TYPES OF CANCER.

THIS IS TOM SHROUT REPORTING FROM CASE WESTERN RESERVE UNIVERSITY, CLEVELAND.