Paraoxonase polymorphism and its effect on male reproductive outcomes among Chinese pesticide factory workers

Abstract

Background Serum paraoxonase has been associated with the metabolism of organophosphate pesticides in humans. Molecular analysis of the human paraoxonase gene (PON1) has revealed that Arg192 homozygotes have a greater detoxifying capability than Gln192 homozygotes. We examined the effects of PON1 genotypes on male reproductive outcomes and its interaction with exposure to organophosphate pesticides. Methods We studied 60 Chinese pesticide‐factory workers and 89 textile‐factory workers who were unexposed to pesticides. The respective allele frequencies of Arg192 and Gln192 were 0.62 and 0.38. Pesticide exposure among 36 exposed subjects and 12 unexposed subjects, regardless of gender, was assessed by personal measurement of pesticide residues over an entire 8‐hr shift and measurement of urinary p‐nitrophenol level over a 24‐hr period. We analyzed semen and hormone data collected from male subjects. Results When the three PON1 genotypes were analyzed separately, a gene dose effect was not detected. We used the unexposed Arg192 homo/heterozygotes as the reference group, and re‐analyzed the data. Exposed Arg192 homo/heterozygotes had significantly lower sperm count (χ2=9.01, P < 0.01) and lower percentage of sperm with normal morphology (χ2=4.18, P < 0.05) than the reference group. Both unexposed Gln192 homozygotes (χ2=4.90, P < 0.05) and exposed Arg192 homo/heterozygotes (χ2=10.00, P < 0.01) showed significantly lower sperm concentrations than the reference group. In addition, exposed Arg192 homo/heterozygotes had significantly higher serum LH levels (χ2=7.94, P < 0.01) than the reference group. Conclusions Because of a small sample size, our findings are highly preliminary. Nevertheless, it calls for further investigation of the interaction between the PON1 genotype and organophosphate pesticide exposure on male reproductive outcomes. Am. J. Ind. Med. 36:379–387, 1999. © 1999 Wiley‐Liss, Inc.

GSTP1 Genetic Polymorphism Is Associated with a Higher Risk of DNA Damage in Pesticide-Exposed Fruit Growers

“…54), whereas it occurred more frequently in sample population from mainland China (62.1%; ref. 30). The frequency of the PON2 311 Ser allele was 82.7%, similarly to that found in a previous study conducted among Chinese controls (82.8%; ref.…”

“…Furthermore, the genetic polymorphisms of human CYP3A5 (25), PON1 (26), PON2 (26), GSTM1 (27), GSTT1 (28), and GSTP1 (29) have been identified. Interestingly, the human PON1 gene is reportedly associated with poor reproductive outcome in Chinese pesticide factory workers (30). In additional to the PON1 gene, the GSTM1 and GSTT1 genes also influence the frequency of chromosome aberrations in lymphocytes of pesticide-exposed greenhouse workers (31).…”

Gene-environment interaction and male reproductive function

“…In Chinese workers, the effects of organophosphate pesticides on semen quality have been studied in relation to polymorphisms in the paraoxonase gene, which is involved in the metabolism of these pesticides [51]. In the Chinese study, organophosphate pesticide exposure was associated with decreased sperm count and sperm concentration, but unexpectedly, exposed men with a variant of the paraoxonase gene encoding for a less efficient detoxifying enzyme had higher sperm counts and better morphology compared with exposed men with the more effective variant.…”

Mapping Health in the Great Lakes Areas of Concern: A User-Friendly Tool for Policy and Decision Makers

“…Hexacholorobenzene, found in Great Lakes waters, may be associated with damage to the structure of the ovary (34) and pesticides have been linked with reproductive failure in animals (36) and humans (37)(38)(39).…”

“…Disorders of the penis, when not idiopathic, can be associated with leukemia, sickle cell disease, pelvic intracavernous injection therapy for impotence, severe vasculitis, and chronic inflammation (41). Pesticides have been linked to reproductive failure in animals (36) and infertility in humans (37,39).…”