Hi all,

I downloaded the STAD project 450k methylation data. The version reported is "Data Release 39.0 - December 04, 2023"; the Samples dataset size is 397.

Unfortunately what I'm noticing is that there is a large number of NAs;

for example on the first and on the second Sample the NAs table are

1st)

FALSE   TRUE 
412169  73408

2nd)

FALSE   TRUE 
412846  72731

on the 396th and on 397th Sample the NAs table are

396th)

FALSE   TRUE 
410016  75561

397th)

FALSE   TRUE 
411597  73980

Is the methylation data structured like this with all these NAs?

What is the normalization method chosen?

Looking forward to hearing from you, Thanks in advance