In one study, 108 regions of the genome were identified to be significantly associated with schizophrenia. Below is a Manhattan plot showing the results from this study. Assuming that none of the causative variants are linked and there is a single causative variant per peak region, how many regions of chromosome 6 with causative variants were identified in this study

The top of the highest peak corresponds to a region of the genome called the MHC locus. This means that of all the variants identified by this study, ____________.

the variant in MHC is observed the most frequently in the affected cohort.

the variant in MHC can cause schizophrenia in a Mendelian fashion.

the variant in MHC is the least likely to be a false positive result.

the variant in MHC has the largest odds ratio.

answer:

i) 4

ii) the variant in MHC is the least likely to be a false positive result. ( C )

Explanation:

The number of regions of chromosome 6 with causative variants identified is 4

While the variant in MHC is the least likely to be a false positive result. this is because, it is the highest peak in of all the causative variants identified in this study (i.e. closely related to the disease) and been the highest peak will make it least likely to return a false positive result.