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Relationship: 405

Title

A descriptive phrase which clearly defines the two KEs being considered and the sequential relationship between them (i.e., which is upstream, and which is downstream). More help

Malformation, Male reproductive tract leads to impaired, Fertility

Upstream event

The causing Key Event (KE) in a Key Event Relationship (KER). More help

Malformation, Male reproductive tract

Downstream event

The responding Key Event (KE) in a Key Event Relationship (KER). More help

impaired, Fertility

Key Event Relationship Overview

The utility of AOPs for regulatory application is defined, to a large extent, by the confidence and precision with which they facilitate extrapolation of data measured at low levels of biological organisation to predicted outcomes at higher levels of organisation and the extent to which they can link biological effect measurements to their specific causes.Within the AOP framework, the predictive relationships that facilitate extrapolation are represented by the KERs. Consequently, the overall WoE for an AOP is a reflection in part, of the level of confidence in the underlying series of KERs it encompasses. Therefore, describing the KERs in an AOP involves assembling and organising the types of information and evidence that defines the scientific basis for inferring the probable change in, or state of, a downstream KE from the known or measured state of an upstream KE. More help

AOPs Referencing Relationship

AOP Name	Adjacency	Weight of Evidence	Quantitative Understanding	Point of Contact	Author Status	OECD Status
PPARα activation in utero leading to impaired fertility in males	adjacent	High		Arthur Author (send email)	Open for citation & comment	Under Review

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KER.In general, this will be dictated by the more restrictive of the two KEs being linked together by the KER. More help

Term	Scientific Term	Evidence	Link
rat	Rattus norvegicus	High	NCBI
human	Homo sapiens	High	NCBI
mice	Mus sp.	Low	NCBI

Sex Applicability

An indication of the the relevant sex for this KER. More help

Life Stage Applicability

An indication of the the relevant life stage(s) for this KER. More help

Key Event Relationship Description

Provides a concise overview of the information given below as well as addressing details that aren’t inherent in the description of the KEs themselves. More help

Impairment in the normal development of the male reproductive tract (e.g. genital abnormality and/or cryptorchidism) can impact on fertility later in life.

Evidence Collection Strategy

Include a description of the approach for identification and assembly of the evidence base for the KER. For evidence identification, include, for example, a description of the sources and dates of information consulted including expert knowledge, databases searched and associated search terms/strings. Include also a description of study screening criteria and methodology, study quality assessment considerations, the data extraction strategy and links to any repositories/databases of relevant references.Tabular summaries and links to relevant supporting documentation are encouraged, wherever possible. More help

Evidence Supporting this KER

Addresses the scientific evidence supporting KERs in an AOP setting the stage for overall assessment of the AOP. More help

Biological Plausibility

Addresses the biological rationale for a connection between KEupstream and KEdownstream. This field can also incorporate additional mechanistic details that help inform the relationship between KEs, this is useful when it is not practical/pragmatic to represent these details as separate KEs due to the difficulty or relative infrequency with which it is likely to be measured. More help

Hypospadias next to cryptorchidism belongs to the most common male reproductive disorders that manifest at birth and may have a common origin in foetal life (Skakkebaek, Rajpert-De Meyts, and Main 2001) and are associated with decreased fertility (Thorup et al. 2010).

Empirical Evidence

Provides specific (citable) evidence that supports the idea of a change in the upstream KE (KEupstream) leading to, or being associated with, a subsequent change in the downstream KE (KEdownstream), assuming the perturbation of KEupstream is sufficient. More help

Human

Asklund et al that semen quality was reduced in men with hypospadias and additional genital disorders, predominately cryptorchidism (Asklund et al. 2010). In another study by Bracka, 25% of 41 hypospadias patients including 26 patients also with cryptorchidism had a lower sperm density (Bracka 1989). Men with a history of cryptorchidism have an increased risk of infertility (Thorup et al. 2010). Eisenberg et al. found shorter AGD among infertile men as compared with fertile men (Eisenberg et al. 2011).

Rat

In rodents in utero exposure to agents known to disrupt androgen mediated pathways corrupts normal male genital development with a decrease in genital length (ie phallus length, AGD) and impaired testosterone and sperm production (Macleod et al. 2010), (Cowin et al. 2010), including exposure to phthalates (NTP 2005).

Uncertainties and Inconsistencies

Addresses inconsistencies or uncertainties in the relationship including the identification of experimental details that may explain apparent deviations from the expected patterns of concordance. More help

Known modulating factors

This table captures specific information on the MF, its properties, how it affects the KER and respective references.1.) What is the modulating factor? Name the factor for which solid evidence exists that it influences this KER. Examples: age, sex, genotype, diet 2.) Details of this modulating factor. Specify which features of this MF are relevant for this KER. Examples: a specific age range or a specific biological age (defined by...); a specific gene mutation or variant, a specific nutrient (deficit or surplus); a sex-specific homone; a certain threshold value (e.g. serum levels of a chemical above...) 3.) Description of how this modulating factor affects this KER. Describe the provable modification of the KER (also quantitatively, if known). Examples: increase or decrease of the magnitude of effect (by a factor of...); change of the time-course of the effect (onset delay by...); alteration of the probability of the effect; increase or decrease of the sensitivity of the downstream effect (by a factor of...) 4.) Provision of supporting scientific evidence for an effect of this MF on this KER. Give a list of references. More help

Quantitative Understanding of the Linkage

Captures information that helps to define how much change in the upstream KE, and/or for how long, is needed to elicit a detectable and defined change in the downstream KE. More help

Response-response Relationship

Provides sources of data that define the response-response relationships between the KEs. More help

Time-scale

Information regarding the approximate time-scale of the changes in KEdownstream relative to changes in KEupstream (i.e., do effects on KEdownstream lag those on KEupstream by seconds, minutes, hours, or days?). More help

Known Feedforward/Feedback loops influencing this KER

Define whether there are known positive or negative feedback mechanisms involved and what is understood about their time-course and homeostatic limits. More help

Domain of Applicability

A free-text section of the KER description that the developers can use to explain their rationale for the taxonomic, life stage, or sex applicability structured terms. More help

Human and Rat see "Empirical Support for Linkage"

References

List of the literature that was cited for this KER description. More help

Asklund, C, T K Jensen, K M Main, T Sobotka, N E Skakkebaek, and N Jørgensen. 2010. “Semen Quality, Reproductive Hormones and Fertility of Men Operated for Hypospadias.” International Journal of Andrology 33 (1) (February): 80–7. doi:10.1111/j.1365-2605.2009.00957.x.

Bracka, A. 1989. “A Long-Term View of Hypospadias.” British Journal of Plastic Surgery 42 (3) (May): 251–5.

Cowin, Prue A, Elspeth Gold, Jasna Aleksova, Moira K O’Bryan, Paul M D Foster, Hamish S Scott, and Gail P Risbridger. 2010. “Vinclozolin Exposure in Utero Induces Postpubertal Prostatitis and Reduces Sperm Production via a Reversible Hormone-Regulated Mechanism.” Endocrinology 151 (2) (February): 783–92. doi:10.1210/en.2009-0982.

Eisenberg, Michael L, Michael H Hsieh, Rustin Chanc Walters, Ross Krasnow, and Larry I Lipshultz. 2011. “The Relationship between Anogenital Distance, Fatherhood, and Fertility in Adult Men.” PloS One 6 (5) (January): e18973. doi:10.1371/journal.pone.0018973.

Macleod, D J, R M Sharpe, M Welsh, M Fisken, H M Scott, G R Hutchison, A J Drake, and S van den Driesche. 2010. “Androgen Action in the Masculinization Programming Window and Development of Male Reproductive Organs.” International Journal of Andrology 33 (2) (April): 279–87. doi:10.1111/j.1365-2605.2009.01005.x.

Mendiola, Jaime, Richard W Stahlhut, Niels Jørgensen, Fan Liu, and Shanna H Swan. 2011. “Shorter Anogenital Distance Predicts Poorer Semen Quality in Young Men in Rochester, New York.” Environmental Health Perspectives 119 (7) (July): 958–63. doi:10.1289/ehp.1103421.

NTP. 2005. “Multigenerational Reproductive Assessment by Continuous Breeding When Diethylhexylphthalate (CAS 117-81-7).”

Skakkebaek, N E, E Rajpert-De Meyts, and K M Main. 2001. “Testicular Dysgenesis Syndrome: An Increasingly Common Developmental Disorder with Environmental Aspects.” Human Reproduction (Oxford, England) 16 (5) (May): 972–8.

Thorup, Jorgen, Robert McLachlan, Dina Cortes, Tamara R. Nation, Adam Balic, Bridget R. Southwell, and John M. Hutson. 2010. “What Is New in Cryptorchidism and Hypospadias - A Critical Review on the Testicular Dysgenesis Hypothesis.” Journal of Pediatric Surgery. doi:10.1016/j.jpedsurg.2010.07.030.