To the Editor:
We read with interest the article by Kim and co-workers (1) describing the analysis of the transforming growth factor beta 1 (TGF-beta 1) -509 C/T gene polymorphism among Korean patients with advanced-stage endometriosis and controls.
The authors assessed the prevalence of the C/C, C/T and T/T genotypes among 485 cases and 352 controls and found no association with endometriosis: CC/CT/TT rates were 29.3%/48.2%/22.5% and 27.3%/50.3%/22.4% for the endometriosis and control groups, respectively. Their results contradict a previous study (2) that found a strong association between endometriosis and the presence of the -509T allele in a Chinese population.
Authors also claim that, to the best of their knowledge, their publication (1) is the second study assessing the TGF-beta 1 -509 C/T gene polymorphism and endometriosis after the study by Hsieh and co-workers (2). We would like to note that the study by Kim et al. (1) is the third study assessing the TGF-beta 1 -509 C/T gene polymorphisms and endometriosis. The second study was published by our group in 2007, in which we enrolled European women (3).
Interestingly, the results of our study (3) are in line with the data from Kim et al. (1), indicating that TGF beta 1 -509 C/T gene polymorphism plays no role in endometriosis [and therefore contradict the Chinese investigation (2)].
Though, comparing the Korean and the European studies (2, 3) it can be observed that large variations in the genotype distribution exist between these two ethnic groups: CC/CT/TT percentages are 27.3%/50.3%/22.4% and 44.1%/47.3%/8.6% in the Korean and European control populations, respectively.
Andrea Romano, Ph.D.
Kim J.A.F. van Kaam, M.D.
Gerard A.J. Dunselman, Ph.D., M.D.
GROW: School for Oncology and Developmental Biology and Department of Obstetrics and Gynaecology
Maastricht University Medical Centre
Maastricht, The Netherlands
1. Kim JJ, Choi YM, Choung SH, Yoon SH, Lee KS, Ku SY, Kim JG, Moon SY 2010 Analysis of the transforming growth factor beta1 gene -509 C/T polymorphism in patients with advanced-stage endometriosis. Fertil Steril 93:2121-4.
2. Hsieh YY, Chang CC, Tsai FJ, Peng CT, Yeh LS, Lin CC 2005 Polymorphism for transforming growth factor beta 1-509 (TGF-B1-509): association with endometriosis. Biochem Genet 43:203-10.
3. van Kaam KJ, Romano A, Dunselman GA, Groothuis PG 2007 Transforming growth factor beta1 gene polymorphism 509C/T in deep infiltrating endometriosis. Reprod Sci 14:367-73.
Published online in Fertility and Sterility doi:10.1016/j.fertnstert.2010.06.022
The Authors Respond:
My colleagues and I have read the comment by Romano et al. directed to our article entitled ‘Analysis of the transforming growth factor 1 gene -509 C/T polymorphism in patients with advanced-stage endometriosis.
I would like to thank Romano et al. for notifying us our mistake. We stated that, to the best of our knowledge, our study is the second article assessing the TGF- 1 -509 C/T gene polymorphism and endometriosis after the study by Hsieh et al., but as soon as we received this comment, we searched PubMed and reviewed the article by Romano et al. entitled ‘Transforming growth factor beta1 gene polymorphism 509C/T in deep infiltrating endometriosis.’ We also agree that this is the second study assessing this issue (Date of publication of the article by Romano et al. was May, 2007, and the date of submission of our article was March 20, 2008)
Interestingly, both studies share a common conclusion indicating that TGF- 1 -509 C/T gene polymorphism plays no role in endometriosis, and therefore contradict the Chinese investigation.
Once more, we thank Romano et al. for pointing out the error in our article.
Young Min Choi, M.D.
Department of Obstetrics & Gynecology
The Institute of Reproductive Medicine and Population Medical Research Center
Seoul National University College of Medicine
Published online in Fertility and Sterility doi:10.1016/j.fertnstert.2010.06.023