There were only two witnesses to today's Gospel scene, Joseph and the angel. So the fact that this story has come down to us at all means that Joseph must have shared with others the choice he made when bringing Jesus into the world. He had to know that tongues would wag, fingers would point and that rumors would spread; both he and Mary would be ridiculed and misunderstood. But, despite that, Joseph chose life.

Like Joseph, many of today’s parents of developmentally challenged children feel misunderstood. They, too, were given a revelation before their babies were born. A sonogram showed them the sex of the fetus and whether there were any obvious abnormalities. Another test revealed certain genetic disorders such as Down syndrome. Sadly, up to 90 percent of women who learned their fetus had Down syndrome terminated their pregnancy, studies suggest. Those who chose to bring their child into this world were often questioned by people, who couldn’t understand why they’d give birth to a disabled baby.

Imagine the relief those parents felt, when Sarah Palin, the Republican candidate for Vice President, held high her five-year old son, Trig - - who has Down syndrome - - and pledged to be their advocate in the White House.

For Christians in both political parties, that had to be a shining moment for the pro life movement. It comes at a time when medical science speaks confidently of the day when doctors will perform gene therapy in the womb, rewriting the destiny of future offspring.

Scientists have already mapped the entire genetic sequence, over 800,000 genes. Some genes have been linked to personality traits such as optimism, assertiveness and anxiety. Other genes have been linked to physical traits such as obesity.

This mind-boggling science raises ethical questions with disturbing implications. For instance, in one survey young couples were asked, “What would you do if you knew your unborn child carried the gene for obesity?” Fifty percent said they would have an abortion.

Just because the child might be obese?

They're talking about people like Thomas Aquinas, J.P. Morgan, Winston Churchill, Teddy Roosevelt, Pope John Paul. They're talking about one in every 12 adults.

The study does not say what might become of children who carry other “undesirable” genes. Children who are too short or too tall or who are simply the wrong sex. Children who don't have designer genes.

The study doesn't say what might happen to a child conceived out of wedlock by a young girl engaged to an older man. The study doesn't speak to that point, but the first chapter of Matthew does. We know what happened because Joseph wanted us to know. When the choice was his, Joseph chose life.