[LETTERHEAD OF GENWORTH FINANCIAL]

                                                                      Exhibit 5

March 16, 2006

Genworth Life and Annuity Insurance Company
6610 West Broad Street
Richmond, Virginia 23230

Re: Genworth Life and Annuity Insurance Company
    Genworth Life & Annuity MVA Separate Account
    Post-Effective Amendment No. 6
    File No. 333-69786

Ladies and Gentlemen:

I serve as Counsel to Genworth Life and Annuity Insurance Company (the
"Company") and its Genworth Life & Annuity MVA Separate Account (the "Separate
Account") with regard to the registration of Guaranteed Fixed Annuity Contracts
(the "Contracts") being filed on Form S-1 under the Securities Act of 1933. I
have examined Post-Effective Amendment No. 6 to the Registration Statement on
Form S-1, including all related documents and exhibits, and have reviewed such
questions of law as I considered necessary and appropriate. On the basis of
such examination and review, it is my opinion that:

1. The Company is a corporation duly organized and validly existing under the
laws of the Commonwealth of Virginia and is duly authorized to sell and issue
the Contracts.

2. The Separate Account has been properly created and is a validly existing
separate account pursuant to the laws of the Commonwealth of Virginia.

The issuance and sale of the Contracts, when issued and sold in the manner
stated in the Registration Statement, will be legal and binding obligations of
the Company in accordance with their terms, except that clearance must be
obtained, or the Contract form must be approved, prior to issuance thereof in
certain jurisdictions, except to the extent limited by bankruptcy, insolvency,
reorganization, moratorium or other similar laws relating to or affecting the
enforcement of creditors' rights generally, and to general principles of
equity, including applicable insurance company insolvency laws.

I express no opinion herein other than as to the law of the Commonwealth of
Virginia. This opinion is rendered as of the date hereof and I assume no
obligation to update or supplement this letter to reflect any circumstances
which may hereafter come to my attention with respect to the opinion and
statements set forth above, including any changes in law or fact (or the effect
thereof on the opinions expressed herein) that hereafter may come to my
attention.

I hereby consent to the filing of this opinion as an exhibit to Amendment No. 6
to the Registration Statement filed on Form S-1 for the Contracts.

Sincerely,

/s/ Heather Harker
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Heather Harker
Vice President and Associate General Counsel