Methods and compositions for predicting drug responses

1. A method of administering warfarin to a subject, the method comprising;

determining the genotype of a human subject in need of warfarin treatment at the position corresponding to 6484 of SEQ ID NO: 1;

administering a maintenance dose of between 4.9 and 6.2 mg/day to a subject determined to have a genotype of C/C at the position corresponding to 6484 of SEQ ID NO: 1; or

administering a maintenance dose of between 4.1 and 4.9 mg/day to a subject determined to have a genotype of C/T at the position corresponding to 6484 of SEQ ID NO:1; or

administering a maintenance dose of between 2.2 and 3.1 mg/day to a subject determined to have a genotype of T/T at the position corresponding to 6484 of SEQ ID NO:1.

2. The method according to claim 1 , wherein said determining comprises:

sequencing a nucleic acid molecule obtained from the subject, the sequence comprising at least the genotype of the nucleotide corresponding to position 6484 of SEQ ID NO:1.

3. The method according to claim 1 , wherein said determining comprises:

detecting, in a hybridization assay, an ability of a nucleic acid molecule obtained from the subject to hybridize to an oligonucleotide probe.

4. The method according to claim 1 , wherein said determining comprises:

detecting, in a PCR-based assay, an ability of oligonucleotide primers to amplify a nucleic acid molecule obtained from the subject.

5. The method according to claim 1 , wherein said determining comprises the use of an allele-specific probe or primer.

6. The method according to claim 3 , wherein said detecting in a hybridization assay comprises:

contacting a nucleic acid molecule derived from a sample obtained from the human subject with an oligonucleotide array comprising oligonucleotide probes that are complementary to sequences comprising either C or T at the position corresponding to 6484 of SEQ ID NO: 1, wherein either the nucleic acid molecule derived from the sample obtained from the human subject or the oligonucleotide probe is conjugated to a detectable label;

detecting signals from the probes of the oligonucleotide array, wherein a detectable signal indicates a nucleic molecule from the sample obtained from the human subject is hybridized to a complementary oligonucleotide probe; and

determining, on the basis of the signals detected from the oligonucleotide array, the subject's genotype at the position corresponding to 6484 of SEQ ID NO: 1.

7. The method according to claim 4 , wherein said detecting in a PCR-based assay comprises:

contacting a nucleic acid molecule derived from a sample obtained from the human subject with a set of oligonucleotide primers comprising a primer which is complementary to sequences comprising either C or T at the position corresponding to 6484 of SEQ ID NO: 1;

amplifying the nucleic acid molecule derived from a sample obtained from the human subject;

detecting the presence or absence of an amplification product resulting from the amplification of the nucleic acid molecule with the set of oligonucleotide primers;

wherein the presence of an amplification product from amplification of the nucleic acid molecule with a set of primers complementary to sequence comprising a C at the position corresponding to 6484 of SEQ ID NO:1 indicates at least one copy of C at that position;

wherein the presence of an amplification product from amplification of the nucleic acid molecule with a set of primers complementary to sequence comprising a T at the position corresponding to 6484 of SEQ ID NO:1 indicates at least one copy of T at that position; and

wherein the presence of an amplification product from amplification of the nucleic acid molecule with both set of primers the presence of both C and T at that position; and

determining, on the presence of the amplification products, the subject's genotype at the position corresponding to 6484 of SEQ ID NO: 1.