1. Carlsen E, Giwercman A, Keiding N, Skakkebaek NE. Evidence for decreasing quality of semen during past 50 years. BMJ 1992; 305(6854):609-613.
2. Tüttelmann F, Rajpert-De Meyts E, Nieschlag E, Simoni M. Gene polymorphisms and male infertility a meta analysis and literature review. Reprod Biomed On line 2007; 15(6): 643-658.
3. Rovio AT, Marchington DR, Donat S, Schuppe HC, Abel J, Fritsche E, Elliott DJ, Laippala P, Ahola AL, McNay D, Harrison RF, Hughes B, Barrett T, Bailey DM, Mehmet D, Jequier AM, Hargreave TB, Kao SH, Cum mins JM, Barton DE, Cooke HJ, Wei YH, Wichmann L, Poulton J, Jacobs HT. Mutations at the mitochondrial DNA polymerase (POLG) locus associated with male infertility. Nat Genet 2001; 29(3): 261-262.
4. Ropp PA, Copeland WC. Cloning and characteriza tion of the human mitochondrial DNA polymerase, DNA polymerase gamma. Genomics 1996; 36(3): 449-458.
5. Rovio A, Tiranti V, Bednarz AL, Suomalainen A, Spelbrink JN, Lecrenier N, Melberg A, Zeviani M, Poulton J, Foury F, Jacobs HT. Analysis of the trinucleo tide CAG repeat from the human mitochondrial DNA polymerase gene in healthy and diseased individuals. Eur J Hum Genet 1999; 7(2): 140-146.
6. Malyarchuk BA, Papuga M, Grzybowski T, Rogozin IB, Wozniak M, Derenko MV, Rychkov SY, Czarny J, Zakharov IA, Miœcicka-Sliwka D. Low variabil ity of the POLG (CAG)n repeat in north Eurasian popula tions. Hum Biol 2005; 77(3): 355-365.
7. Jensen M, Leffers H, Petersen JH, Nyboe Andersen A, Jørgensen N, Carlsen E, Jensen TK, Skakkebaek NE, Rajpert-De Meyts E. Frequent polymorphism of the mito chondrial DNA polymerase gamma gene (POLG) in patients with normal spermiograms and unexplained sub fertility. Hum Reprod 2004;19(1): 65-70.
8. Krausz C, Guarducci E, Becherini L, Degl’Innocenti S, Gerace L, Balercia G, Forti G. The clinical significance of the POLG gene polymorphismin male infertility. J Clin Endocrinol Metab 2004; 89(9): 4292-4297.
9. Aknin-Seifer IE, Touraine RL, Lejeune H, Jimenez C, Chouteau J, Siffroi JP, McElreavey K, Bienvenu T, Patrat C, Levy R. Is the CAG repeat of mitochondrial DNA polymerase gamma (POLG) associated with male infertility? A multi-centre French study. Hum Reprod 2005; 20(3): 736-740.
10. Brusco A, Michielotto C, Gatta V, Foresta C, Matullo G, Zeviani M, Ferrari G, Dragone E, Calabrese G, Rossato M, Stuppia L, Migone N. The polymorphic poly glutamine repeat in the mitochondrial DNA polymerase gamma gene is not associated with oligozoospermia. J Endocrinol Invest 2006; 29(1):1-4.
11. Yao N, Zheng JF, Peng YF, Li ZX, Peng ZQ, Jin XH, Ma X. CAG repeats of DNA polymerase gamma in Chinese males and relationship of idiopathic male infertil ity to CAG repeats. Zhonghua Nan Ke Xue 2006; 12(8): 681-684.
12. World Health Organization. Laboratory Manual for the Examination of Human Semen and Semen Cervical Mucus Interaction, 4th ed. Cambridge: Cambridge Univer sity Press. 1999.
13. Plaseski T, Dimitrovski C, Kocevska B, Efremov DG, Plaseska-Karanfilska D. The prevalence of Y chromo some microdeletions among infertile males from the Republic of Macedonia. Balkan J Med Genet 2003; 6(1&2): 39-44.
14. Plaseski T, Noveski P, Kocevska B, Dimitrovski C, Efremov GD, Plaseska-Karanfilska D. AZF deletions in infertile men from the Republic of Macedonia. Prilozi 2006; 27(1): 5-16.
15. Efremov GD, Dimovski AJ, Plaseska-Karanfilska D, Simjanovska L, Sukarova E, Koceva S. Isolation of genomic DNA from mammalian cells. In: Efremov GD, Ed. A Laboratory Manual, 3rd ed. Skopje: Macedonian Academy of Sciences and Arts. 1999; 1-3.
16. Spelbrink JN, Toivonen JM, Hakkaart GA, Kurkela JM, Cooper HM, Lehtinen SK, Lecrenier N, Back JW, Speijer D, Foury F, Jacobs HT. In vivo functional analysis of the human mitochondrial DNA polymerase POLG expressed in cultured human cells. J Biol Chem. 2000; 275(32): 24818-24828.