Long PCR primers

[Wellcome Trust, Nairobi.]

Dear Colleagues,

If there any risk of amplifying a fragment DNA with primer which are 50
to 60 pb. Actually, I want to introduce a enzyme restriction site in
these primers so that I can easily  detected them in agore or Acrylamide
gel. Therefore I do need longer primers. But I wandering about doing a
PCR such long oligonucleotides.
My regards,

-- 
Wellcome Trust Research Labs, 
PO Box 43640,
Nairobi, Kenya.
Tel 254 (2) 725390, Fax 254 (2) 711673
E-mail: wellcome at users.africaonline.co.ke