300 samples from different infection sourcel for a patients and revisers in Azadi hospital, Kirkuk generic hospital, and children hospital, from various ages for both genders, to isolate Escherichia coli bacteria and diagnosis it, and study the genetic variety which distribution to clinical samples by (140) urine samples, (45) diarrhea samples, (40) wound swab, (40) burn swab, and (35) from otitis media infection.
 The growth isolation on the different cultural media was diagnosed from the appearance, microscopical, and cultural characteristics. The results the diagnosis showed that (75) clinical isolation about (38.65%) refers to E. coli bacteria distributed by (9) isolation at ratio (31%) from the burn swab, (6) isolation at ratio (26.1) from wound swab, (4) isolation from otitis media infection (19%), (13) isolation from the stool about (40.6%), and (43) isolation (84.3%) from the urinary tract infection (UTI).
 The sensitivity of the clinical and ecological isolations was studied for nine antibiotics from different antibiotics, broadly. Where the highest resistance for the antibiotics in the clinical isolations to both (ampicillin and cephalexin) reaching in the rate of (97.3%) and (92%), respectively. While the lowest resistance rate for the clinical isolations was to the (Amikacin) in the rate of (17.3%).
 It has been selected 24 clinical isolations, and 24 ecological isolations from E. coli isolations depending on here resistance to many of antibiotics. To study the genetic variation for these isolations and the genetic markers it has been used a type of molecular markers which is depending on PCR technical it is: randomly Amplified polymorphic DNA (RAPD).