From the excellent book based on the Reformed Presbyterian Church of North America (RPCNA) study committee on sexual orientation:
The present condition of human nature is, as Scripture teaches us, disordered from its proper design, and the true depth of its brokenness is undoubtedly beyond our comprehension (Jer. 17:9). However, we confess with Scripture that the creation order which God pronounced to be objectively "good," before human nature became burdened with many lusts and confusions of all kinds,constitutes two genders that are sexually oriented for one another. If science shows us that sexual disorders are more deeply enmeshed in human biology than the church has traditionally understood, this ought to stir our concern for even greater understanding and compassion for those who experience these desires; however, it does not change the fact that such inclinations are contrary to human nature as God designed it - and as he is redeeming it.