Oct. 27, 2009 -- Humans may owe the gift of gab to a newly discovered gene that helps keeps vocal pipes limber.

Researchers discovered the gene, dubbed tospeak, in an Australian family with a speaking disorder. Many of the women in the family have weak, husky voices, while several of their male relatives cannot speak above a whisper, reported Raymond Clarke of the University of New South Wales' St. George Hospital in Kogarah, Australia, October 21 at the annual meeting of the American Society of Human Genetics.

Clarke and his colleagues traced the source of the family's disorder to a region of chromosome 8. Part of the chromosome had been rearranged, causing a break in the tospeak gene. Tospeak probably doesn't code for a protein, Clarke says. The gene is sprinkled with stop signals and its RNA product doesn't resemble other RNAs that have specific functions in the cell. But production of the tospeak RNA seems to be important for proper development of the larynx.

Members of the family who have the speaking problem have short, thick vocal cords that don't vibrate properly. Some of the family members also have fused bones in the wrists and feet, known as the carpals and tarsals, and fused vertebrae in their spines. All of the defects may be linked to a breakdown in relations between tospeak and a neighboring gene, known as GDF6, the researchers report.