Genetic Susceptibility and Pathogenesis of Hypospadias

Boys with hypospadias had shorter anogenital distance (4.64 vs 5.33 cm); maternal age ≥34 correlated with severe cases

Journal: Biochemical Genetics | Published: 2025-07-15 | Type: Journal Article, Review | PMID: 40663283 Authors: Ajayi AF, Oyowvi MO, Akanbi GB, Ajayi LO, Jegede AJ (Ladoke Akintola University of Technology / Adeleke University, Nigeria) Funding/COI: Not listed; authors declare no competing interests

Summary

This paper presents a case-control study of 52 boys with hypospadias versus 30 controls at Suez Canal University Hospital (2018–2019), measuring anogenital distance (AGD) and correlating it with hypospadias severity and maternal age. Boys with hypospadias had significantly shorter AGD, and older maternal age tracked with both shorter AGD and more severe anatomical defect. However, there is a fundamental structural problem: the abstract describes a narrative review of genome-wide association study (GWAS) literature, while the methods, results, and conclusion describe an entirely different original case-control study — they read as two separate papers stitched together, with neither section matching the other.

Claims

• Mean AGD was 4.64 cm in hypospadias boys vs. 5.33 cm in controls (p = 0.011)
• Hypospadias severity distribution: 40.4% mild (GMS 3–6), 38.5% moderate (7–9), 21.1% severe (10–12)
• Each additional year of maternal age was associated with a 0.07 cm decrease in AGD (regression, p < 0.001)
• Maternal age ≥34 years significantly correlated with severe hypospadias (positive correlation with GMS score, p < 0.001)
• Short AGD inversely correlated with GMS score — shorter AGD, worse anatomical severity (p < 0.001)
• Incidence of hypospadias stated as 1 in 300 live births (cited from prior literature, not measured here)
• Abstract separately claims that GWAS has identified novel genetic loci with modest individual effect sizes on hypospadias risk

Study Quality

This is a small case-control study — 52 cases and 30 controls — conducted at a single hospital in Egypt over 18 months. Group matching is imperfect: the authors note no statistically significant difference between groups in maternal age, child age, or child weight, which suggests reasonable balance, but 30 controls is underpowered for meaningful subgroup analysis. AGD was measured with a ruler in lithotomy position, which is a crude but reproducible method. Severity was graded using the GMS score, a validated tool. Statistical methods (t-test, Pearson/Spearman correlation, regression) are appropriate for the data type.

The abstract and full-text body are clearly from two different papers or drafts — the abstract describes a review of genetic/GWAS literature with no mention of AGD, case-control design, or Egyptian patients, while the methods section describes exactly that. This is either a submission error or editorial failure, and it undermines confidence in the published record.

Red Flags

• Abstract/body mismatch: The abstract reviews genetic susceptibility and GWAS findings; the methods, results, and conclusion report an AGD case-control study. These are not the same paper.
• N = 82 total: 52 cases, 30 controls. Severely underpowered for genetic or molecular claims.
• Single-center, single-country: Suez Canal University Hospital, Egypt. External validity is limited.
• No hormonal measurements: Claims about androgen disruption and AGD are made without measuring testosterone or endocrine disruptors in this cohort.
• No funding disclosed: No statement on who paid for the study.
• Maternal age confounding: Maternal age effect on AGD was present in both groups — the mechanism may not be hypospadias-specific.
• Regression truncated: The regression result is cut off mid-sentence in the provided text ("every 1-year increase in the child age was associate...").
• Exclusions introduce bias: Excluding boys with prior penile surgery or hormonal treatment could skew the severity distribution toward less-treated, potentially milder cases.

Strengths

• AGD measurement is a biologically meaningful proxy for prenatal androgen exposure
• GMS severity scoring is validated and consistently applied
• Groups are well-balanced on age and weight
• Pearson and Spearman correlations are correctly matched to data distribution
• Findings on AGD and hypospadias severity are consistent with prior literature

Verdict

The AGD findings here — shorter anogenital distance in hypospadias boys, worsening with maternal age — are plausible and consistent with existing evidence on the male programming window and androgen disruption. But a study of 82 children at one hospital produces hypothesis-generating data, not conclusions, and the disconnect between the abstract (a GWAS literature review) and the body (a ruler-and-ruler case-control study) is a serious editorial failure that a peer reviewer should have caught. Read it as a small confirmatory signal, not as new science. The genetic review component promised in the title and abstract does not appear to exist in the published text.