Skip to main content
Sexually Transmitted Infections logoLink to Sexually Transmitted Infections
. 2004 Aug;80(4):286–288. doi: 10.1136/sti.2003.006775

The diversity of the opa gene in gonococcal isolates from men who have sex with men

F Howie 1, H Young 1, A McMillan 1
PMCID: PMC1744858  PMID: 15295127

Abstract

Objectives: To use a molecular typing method (opa-typing) to characterise gonococcal isolates obtained from men who have sex with men (MSM) attending a genitourinary medicine (GUM) clinic in Edinburgh during 2001. To compare the results of opa-typing with A/S (auxotype/serovar) phenotyping, and with epidemiological information obtained by contact tracing.

Methods: Isolates were opa-typed by a PCR-RFLP method where the restriction fragments resulting from digestion with three separate restriction enzymes were resolved by polyacrylamide gel electrophoresis. Isolates were considered to have the same opa-type if the band patterns were identical or if they differed by one band between the three digestions.

Results: 40 opa-types were detected from a collection of 73 gonococcal isolates from 61 patients. 26 opa-types were unique, being found in one individual each, 14 different opa-types were found in more than one patient. Opa-typing was found to have a discrimination index (DI) of 0.96, compared to a DI of 0.87 for A/S phenotyping, indicating that opa-typing is better at discriminating between unrelated isolates. Opa-typing confirmed three epidemiological links established by contact tracing, and uncovered a further 13 clusters of isolates.

Conclusions: Opa-typing is a more discriminative method than A/S phenotyping when determining relatedness in gonococcal isolates. The ability of opa-typing to identify sexual networks not disclosed by contact tracing and conventional phenotyping make it a useful method for studying the spread of gonorrhoea with the potential to contribute to the control of this infection.

Full Text

The Full Text of this article is available as a PDF (70.4 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Copley C. G., Egglestone S. I. Auxotyping of Neisseria gonorrhoeae isolated in the United Kingdom. J Med Microbiol. 1983 Aug;16(3):295–302. doi: 10.1099/00222615-16-3-295. [DOI] [PubMed] [Google Scholar]
  2. Day S., Ward H., Ison C., Bell G., Weber J. Sexual networks: the integration of social and genetic data. Soc Sci Med. 1998 Dec;47(12):1981–1992. doi: 10.1016/s0277-9536(98)00306-2. [DOI] [PubMed] [Google Scholar]
  3. Dehio C., Gray-Owen S. D., Meyer T. F. The role of neisserial Opa proteins in interactions with host cells. Trends Microbiol. 1998 Dec;6(12):489–495. doi: 10.1016/s0966-842x(98)01365-1. [DOI] [PubMed] [Google Scholar]
  4. Dillon J. A., Rahman M., Yeung K. H. Discriminatory power of typing schemes based on Simpson's index of diversity for Neisseria gonorrhoeae. J Clin Microbiol. 1993 Oct;31(10):2831–2833. doi: 10.1128/jcm.31.10.2831-2833.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Ison C. A. Genotyping of Neisseria gonorrhoeae. Curr Opin Infect Dis. 1998 Feb;11(1):43–46. doi: 10.1097/00001432-199802000-00010. [DOI] [PubMed] [Google Scholar]
  6. Meyer T. F. Pathogenic neisseriae: complexity of pathogen-host cell interplay. Clin Infect Dis. 1999 Mar;28(3):433–441. doi: 10.1086/515160. [DOI] [PubMed] [Google Scholar]
  7. Moyes A., Young H. Epidemiological typing of Neisseria gonorrhoeae: a comparative analysis of three monoclonal antibody serotyping panels. Eur J Epidemiol. 1991 Jul;7(4):311–319. doi: 10.1007/BF00144994. [DOI] [PubMed] [Google Scholar]
  8. O'Rourke M., Ison C. A., Renton A. M., Spratt B. G. Opa-typing: a high-resolution tool for studying the epidemiology of gonorrhoea. Mol Microbiol. 1995 Sep;17(5):865–875. doi: 10.1111/j.1365-2958.1995.mmi_17050865.x. [DOI] [PubMed] [Google Scholar]
  9. Palmer H. M., Leeming J. P., Turner A. Investigation of an outbreak of ciprofloxacin-resistant Neisseria gonorrhoeae using a simplified opa-typing method. Epidemiol Infect. 2001 Apr;126(2):219–224. doi: 10.1017/s0950268801005209. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Van Looveren M., Ison C. A., Ieven M., Vandamme P., Martin I. M., Vermeulen K., Renton A., Goossens H. Evaluation of the discriminatory power of typing methods for Neisseria gonorrhoeae. J Clin Microbiol. 1999 Jul;37(7):2183–2188. doi: 10.1128/jcm.37.7.2183-2188.1999. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Ward H., Ison C. A., Day S. E., Martin I., Ghani A. C., Garnett G. P., Bell G., Kinghorn G., Weber J. N. A prospective social and molecular investigation of gonococcal transmission. Lancet. 2000 Nov 25;356(9244):1812–1817. doi: 10.1016/S0140-6736(00)03234-7. [DOI] [PubMed] [Google Scholar]
  12. van Duynhoven Y. T. The epidemiology of Neisseria gonorrhoeae in Europe. Microbes Infect. 1999 May;1(6):455–464. doi: 10.1016/s1286-4579(99)80049-5. [DOI] [PubMed] [Google Scholar]

Articles from Sexually Transmitted Infections are provided here courtesy of BMJ Publishing Group

RESOURCES