In this article, Dr. Morris writes about the incarnation of the Son of God. His premise is that since through genetic mutations, humans have through the generations inherited physical defects, the Lord Jesus could not have come forth from one of the Virgin Mary's ova. Mary's ova were defective, as all human ova; therefore, Mary could not in any way be the human source of our Saviour.
Morris is quite clear on his position. He says:
Therefore, even though He was nurtured in Mary's womb for nine months and born without her ever knowing a man, it was also necessary for all this to have been preceded by supernatural intervention, to prevent His receiving any actual genetic inheritance through her. The body growing in Mary's womb must have been specially created in full perfection, and placed there by the Holy Spirit, in order for it to be free of inherent sin damage. ... His body formed neither of the seed of the man nor the egg of the woman, but grown from a unique Seed planted in the woman's body by God Himself.
This is the ancient heresy of Docetism (that Jesus only appeared to be human while he was not truly human). John, in his first letter, takes this heresy on (see the opening verses of the letter).
The Anabaptists of the 1500s trotted this heresy out again. Article 18 of the Belgic Confession repudiates the heresy. Our Saviour is both true God and true man. He was formed from one of Mary's ova. God broke into the human race and began a new work by conceiving the Son of God in the womb of Mary, but by using an altogether human ovum. If this were not so, we'd be eternally lost (see also Lord's Days 5 & 6 of the Heidelberg Catechism).
Jesus was sinless, but that does not mean he was physically perfect. Isaiah 53:4 says, "Surely he took up our infirmities and carried our sorrows, yet we considered him stricken by God, smitten by him, and afflicted." Those verbs are used in Genesis 12:17 and 2 Kings 15:5 to refer to people falling ill. Our salvation is not in that Jesus did not inherit any physical human weakness through Mary's genes; rather, our salvation is in the glorious truth that the eternal Son of God, while remaining God, became a true man with all the physical attendant weaknesses, sin excepted, and therefore was qualified to be the Lamb of God that takes away the sin of the world.
Dr. Morris espoused a heretical view of the incarnation, i.e., of the human origin of our Saviour. I suspect that his incorrect view of the human origin of Jesus bleeds over to a questionable view of the human origin of mankind, and perhaps a questionable view of creation. He tied it all together. Morris's and ICR's view of creation is very popular in conservative Christian circles of North America. One likely does not do well to adopt uncritically these views.