Department of Epidemiology Research, Statens Serum Institute, Copenhagen S, Denmark.
Epidemiology. 2010 Jan;21(1):109-13. doi: 10.1097/EDE.0b013e3181c15a50.
It has been suggested that cryptorchidism and hypospadias may be the result of a common pathologic pathway that causes testicular dysgenesis during fetal life. To address the potential heritability of this pathway, we specifically examined to what extent a family history of cryptorchidism increases the risk of developing hypospadias and vice versa.
By using Danish health registers, we identified 27,762 boys diagnosed with cryptorchidism and 4832 boys diagnosed with hypospadias in a cohort of 1,018,517 boys born during 1977-2005. Using binomial log-linear regression, we estimated risk ratios of cryptorchidism and hypospadias in male twin pairs and first-, second-, and third-degree relatives with a family history of hypospadias and cryptorchidism, respectively.
After adjusting for birth period and personal hypospadias/cryptorchidism status, there was little evidence of increased risk of cryptorchidism given a family history of hypospadias, and vice versa. However, cryptorchidism and hypospadias was associated on an individual level.
We found no persuasive evidence that a family history of hypospadias increases the risk of cryptorchidism and vice versa. Thus, we found no support for shared heritability of hypospadias and cryptorchidism.
有人提出隐睾症和尿道下裂可能是导致胎儿期睾丸发育不良的共同病理途径的结果。为了探讨该途径的潜在遗传性，我们专门研究了家族史中隐睾症增加发生尿道下裂的风险，反之亦然。
通过使用丹麦健康登记，我们在 1977 年至 2005 年间出生的 1018517 名男孩中，确定了 27762 名患有隐睾症的男孩和 4832 名患有尿道下裂的男孩。我们使用二项式对数线性回归，估计了具有家族史的尿道下裂和隐睾症的男性双胞胎和一级、二级和三级亲属中尿道下裂和隐睾症的风险比。
在调整了出生时期和个人尿道下裂/隐睾症状况后，有家族史的尿道下裂患者发生隐睾症的风险几乎没有增加，反之亦然。然而，隐睾症和尿道下裂在个体层面上是相关的。
我们没有发现令人信服的证据表明家族史中的尿道下裂会增加隐睾症的风险，反之亦然。因此，我们没有发现尿道下裂和隐睾症具有共同遗传性的支持证据。
