Washington (CNN) — The House Ethics Committee announced Monday that it is launching a formal investigation of Nevada Democratic Rep. Shelley Berkley, a seven-term House member who is running for a U.S. Senate seat.

Berkley is facing questions about whether her efforts to block a federal agency from closing a kidney transplant center at a Las Vegas hospital conflicted with congressional ethics rules. Her husband, Dr. Larry Lehrner, is a nephrologist and had a contract with the University Medical Center.

Ethics Committee Chairman Rep. Jo Bonner, R-Alabama, issued a joint statement with the panel’s top Democrat, Rep. Linda Sanchez, D-California, that stated the committee voted unanimously to create an investigative subcommittee “to determine whether Rep. Shelley Berkley violated the Code of Official Conduct or any law, rule, regulation or other applicable standard of conduct in the performance of her duties or the discharge of her responsibilities, with respect to alleged communications and activities with or on behalf of entities in which Rep. Berkley’s husband had a financial interest.”

Berkley is running against Republican Sen. Dean Heller, a former House colleague who was appointed to fill the seat after Nevada GOP Sen. John Ensign resigned after his own ethics problems last year.

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Berkley noted that the Nevada delegation, which Heller was a part of in 2008, worked together to prevent the kidney transplant center from being closed.

Asked if she had any regrets about how