hands and clothing of each person for signs of blood or struggle and then checking the bottoms of their shoes for signs of blood or residue from the thin layer of sawdust at the murder scene. Aiden swabbed the inside of each person’s cheek, bagged the swab and sealed and marked the see-through bag.
DNA, deoxyribonucleic acid, is composed of tightly bound strands called chromosomes. Humans have forty-six paired chromosomes, twenty-three from each parent. Two of these chromosomes decide gender. About thirty thousand genes are attached to each DNA strand. Among other things, genes make up the blueprint for who we are, how we function, our development and growth. No two samples of DNA are exactly alike.
Stella scanned each person with a portable Alternative Light Source. There were traces of blood on only one person in the group, a hefty dark-haired well-groomed young man who identified himself as Earl Katz.
“You have fresh blood on your hands,” said Stella.
The young man, who towered over the two women, said, “Yes. A woman with a broken nose bled on me,” he said. “Domestic disturbance. I’m a police officer. I got off duty about an hour ago, changed clothes, showered, took my uniform to the cleaner.”
“We’ll check,” said Stella.
“I’m sure you will,” said Earl Katz. “You wouldn’t be doing your job if you didn’t.”
Joshua was last and best—traces of blood on both hands and the bottoms of his shoes and what appeared to be patches of sawdust. Stella took samples of the blood and dust from the shoes.
“Want to explain this?” Stella asked, holding up the bags containing blood samples and samples of the sawdust.
“I prefer not to,” said Joshua.
Stella took him in for questioning.
Medical Examiner Sheldon Hawkes was known to occasionally engage in gallows humor, but not today. He had the corpse of Becky Vorhees on the table before him. He had three more corpses in the sliding cabinets against the wall. It would be a long morning. Hawkes, an African-American, had recently been having dreams of walking through tall grass under a sun that looked too close. Ahead he could hear voices speaking in a language he didn’t understand but was sure he once had. Hawkes wanted to run toward the voices but it was too hot. He was too tired. He finally made it through the grass and in the broad open space before him, three young bare-chested black men stood over a dead and bloody lion. The three men welcomed Hawkes, who moved toward them, knowing that his goal was the dead lion. It wasn’t a bad dream at all.
Jane Parsons, who wore a white lab coat, blond hair dangling well-brushed down her neck, looked at the samples lined up on the large table in front of her. There were more than twenty samples. For years commercial laboratories had taken three to six weeks to run a DNA test. Gradually the testing time came down to three to seven days. Jane had cut the time to two days. If the samples were piling up and the CSI investigators were in a hurry, she could get it down to a day.
“Start with the daughter’s blood,” said Mac, leaning over her shoulder.
Was she wearing perfume? No. It was a combination of shampoo and conditioner. He backed away before…Jane looked over her shoulder at him.
“You all right?” she asked.
“Fine,” said Mac. “How long will it take?”
“For all of this?” she said, looking at the table. “Two days. Can the budget take it?”
“It’ll have to,” he said, turning and walking across the room and through the glass doors.
Microscope in front of her, samples on her right, Jane began her work. She had the name of the willing or unwilling donor of each sample. She knew some of the donors had been murdered and others might be murderers. What she couldn’t do, didn’t want to do, was put bodies and faces and lives into the laboratory samples.
Using phenol and chloroform, she extracted the DNA from the first sample. She then precipitated the DNA with