next if ($chromosome =~ /^chrM/);

You're very close, you just need to use the "binding operator" =~ instead of = and your code works. See also perlrequick and perlretut.

Note that if you're using warnings, which you should, you should have gotten a warning "Use of uninitialized value $_ in pattern match (m//)". See also Use strict and warnings.

BTW, please enclose your sample input data in <code> tags as well (not <p>).

In reply to Re: Trouble skipping lines using Perl by haukex
in thread Trouble skipping lines using Perl by LeBran

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