Cochran–Armitage test results
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2.1 years ago
Eliza ▴ 40

Hi , im trying to preform Cochran–Armitage test on SNP data of 21 patients to find assosiation between disease sevirity( HIGH,MILD) and snp. for every snp im preforming the test and my gouls is to get for every sno the pvalue . for this im using the CATT function in R (https://search.r-project.org/CRAN/refmans/CATT/html/CATT.html) or this one :

catt <-
  function(y, x, score = c(0, 1, 2)) {
    miss <- unique(c(which(is.na(y)), which(is.na(x))))
    n.miss <- length(miss)
    if(n.miss > 0) {
      y <- y[-miss]
      x <- x[-miss]
    }
    if(!all((y == 0) | (y == 1))) 
      stop("y should be only 0 or 1.")
    if(!all((x == 0) | (x == 1) |(x == 2))) 
      stop("x should be only 0, 1 or 2.")
    ca <- x [y == 1]
    co <- x [y == 0]
    htca <- table(ca)
    htco <- table(co)
    A <- matrix(0, 2, 3)
    colnames(A) <- c(0, 1, 2)
    rownames(A) <- c(0, 1)
    A[1, names(htca)] <- htca
    A[2, names(htco)] <- htco
    ptt <- prop.trend.test(A[1, ], colSums(A), score = score)
     res=list("2x3-table" = A, 
                #chisq = as.numeric(ptt$statistic), 
                #df = as.numeric(ptt$parameter), 
              p.value=as.numeric(ptt$p.value))
                #n.miss = n.miss)
    return(res)
    }

both result are the same . in my data i have an encoding column for the SNP (hetro=1,homo=2) when my data looks like this for example :

is_severe                   encoding
0                                   2
1                                    1

it gives me the pvalue:

The Cochran-Armitage Trend Test

data:  The type of data is variable!
Z = 1.414, p-value = 0.1573

$`2x3-table`
  0 1 2
0 0 1 0
1 0 0 1

but when my data looks like this:

 is_severe           encoding
0                              2
0                              1
print(catt(sn$ï..is_severe,sn$encoding))
Error in lm.wfit(x, y, w, offset = offset, singular.ok = singular.ok,  : 
  NA/NaN/Inf in 'x'
> print(CATT(sn$ï..is_severe,sn$encoding))
Error in `[.default`(tbl, 2, ) : subscript out of bounds

also when data looks like this

  is_severe           encoding
    0                              1
    0                              1

it returns the same result

 print(catt(sn$ï..is_severe,sn$encoding))
Error in lm.wfit(x, y, w, offset = offset, singular.ok = singular.ok,  : 
  NA/NaN/Inf in 'x'
> print(CATT(sn$ï..is_severe,sn$encoding))
Error in `[.default`(tbl, 2, ) : subscript out of bounds
> 

im new to genatics and i dont know how to fix this or what should i do with my data in order for the test to work on all SNPs and not part of them . thank you:)

test SNP Armitage VCF • 417 views
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