how to avoid rounding off the numbers when inputting the files

Question

I have two files and I am checking its correlation. But while inputing the files it round off the value or keep the number till 5 digit after decimal. I want to keep all the digits and not let R round it off.

expr = read.table(file = "residuals_expression.txt", header = TRUE, sep = "\t" )


GTEX-111CU  GTEX-111CU  0.1666530378417794

Its rounding it to 0.1666530

Is there any way to prevent this round off? Thank you.