NEW YORK (Reuters) - Applications for U.S. home mortgages slipped last week, even as interest rates also eased, an industry group said on Wednesday.

The Mortgage Bankers Association said its seasonally adjusted index of mortgage application activity, which includes both refinancing and home purchase demand, fell 2.9 percent in the week ended Jan 27.

The MBA's seasonally adjusted index of refinancing applications slipped 3.6 percent, while the gauge of loan requests for home purchases gave up 1.7 percent.

The refinance share of total mortgage activity eased to 80.0 percent of applications from 81.3 percent.

Although application volume fell for the week, refinance volume remains high with survey respondents saying the government's expanded Home Affordable Refinance Program (HARP) contributed to about 10 percent of activity, MBA said.

The Obama administration recently revamped HARP to make it easier for underwater homeowners with government-backed loans to refinance their mortgages.

Fixed 30-year mortgage rates averaged 4.09 percent, down 2 basis points from 4.11 percent the week before.

MBA said the decline in mortgage rates came as longer-term Treasuries rates dropped after the Federal Reserve said it would keep likely rates on hold until late 2014, longer than the market had expected.

The survey covers over 75 percent of U.S. retail residential mortgage applications, according to MBA.

(Reporting By Leah Schnurr; Editing by Diane Craft)