Patent ID: 11929243
Assignee: QUEST DIAGNOSTICS INVESTMENTS INCORPORATED
Field: Measurement (Instruments)
Classification: CPC G  H  B | IPC B  G  H

Claim 0:
1. A method for determining the apolipoprotein E (ApoE) phenotype in a sample, said method comprising:
(a) purifying ApoE in the sample;
(b) ionizing ApoE in the sample to produce one or more ion(s) of ApoE;
(c) detecting the ion(s) from step (b) by mass spectrometry; and
(d) determining the phenotype of ApoE allele(s) present in the sample from the ions detected in step (c), wherein the phenotypes determined is ApoE2/ApoE3, ApoE2/ApoE4, ApoE3/ApoE3, ApoE3/ApoE4, or ApoE4/ApoE4;
wherein:
the sample comprises a body fluid;
ApoE2/ApoE3 phenotype is determined by the detection of fragment ions having mass/charge ratios of 374.42±0.5, 502.55±0.5, 665.72±0.5, 835.93±0.5, 866.99±0.5 and 982.08±0.5,
ApoE2/ApoE4 phenotype is determined by the detection of fragment ions having mass/charge ratios of 374.42±0.5, 892.96±0.5, 502.55±0.5, 649.74±0.5, 665.72±0.5, 835.93±0.5, 866.99±0.5, and 982.08±0.5,
ApoE3/ApoE3 phenotype is determined by the detection of fragment ions having mass/charge ratios of 374.42±0.5, 502.55±0.5, 866.99±0.5 and 982.08±0.5,
ApoE3/ApoE4 phenotype is determined by the detection of fragment ions having mass/charge ratios of 374.42±0.5, 892.96±0.5, 502.55±0.5, 649.74±0.5, 866.99±0.5, and 982.08±0.5, and/or
ApoE4/ApoE4 phenotype is determined by the detection of fragment ions having mass/charge ratios of 374.42±0.5, 892.96±0.5, 502.55±0.5, and 649.74±0.5.