Kathy Reichs - Grave Secrets

Ryan stopped blowing smoke from his fingertip and stared at the phone.

“Meaning they were consistent?”

“Meaning they were identical.”

“Thank you.”

I disconnected.

“You can holster your weapon.”

Ryan dropped his gun pantomime and placed hands on hips.

“How can he be so sure it’s a match?”

“It’s his business to be sure.”

“The hair’s been in a friggin’ septic tank.” Ryan’s tone oozed skepticism.

“Do you know anything about DNA?”

“What I don’t know I have a feeling I’m about to learn.” He raised a hand, palm out. “The five-minute version. Please.”

“Do you know what a DNA molecule looks like?” I asked.

“A spiral staircase.”

“Very good. Sugars and phosphates form the handrails, and bases form the steps. How can I bring this down to your level?”

Ryan opened his mouth to object, but I cut him off.

“Think of the bases as Legos that only come in four colors. If there’s a red Lego on one half of a step, there’s always a blue Lego on the other. Green pairs with yellow.”

“And not everyone has the same color pattern at a particular place.”

“You’re not as dumb as you look, Ryan. When multiple variations exist for a sequence of steps, it’s called a polymorphism. When a position has extreme numbers of variants, maybe hundreds, it’s called a hypervariable region.”

“Like Manhattan.”

“Did you want this in five minutes?”

Ryan held up both palms.

“Variations, or polymorphisms, can occur in the sequence of colors, or in the number of times those colors are repeated between any two specific steps. You with me?”

“A particular fragment can vary in pattern or length.”

“The first technique that was adapted for forensic DNA analysis was called RFLP, Restriction Fragment Length Polymorphism. RFLP analysis determines variation in the length of a defined DNA fragment.”

“Produces that thing that looks like a grocery store bar code.”

“It’s called an autoradiograph. Unfortunately, RFLP requires better-quality DNA than many crime scene samples provide. That’s why PCR was such a breakthrough.”

“Amplification.”

“Exactly. Without going into details—”

“But I love it when you talk dirty.” Ryan reached out and touched my nose. I brushed his hand away.

“Polymerase Chain Reaction is a technique for increasing the amount of DNA available for analysis. A defined sequence of Lego steps is copied millions of times.”

“Genetic Xeroxing.”

“Except that with each round the number of copies doubles, so the increase in DNA is geometric. The drawback to PCR analysis is that fewer variable regions have been identified, and each tends to show less variation.”

“So you’re able to use PCR with crummier DNA, but the power of discrimination is lower.”

“Historically that’s been the case.”

“What’s this mitochondrial stuff?”

“RFLP and PCR—and there are other procedures—use genomic DNA, which resides in the cell nucleus. Additional bits of genetic material are found in the mitochondria, small compartments in the cell where respiration takes place. The mitochondrial genome is smaller, slightly over sixteen thousand bases, and forms a circle, not a staircase. There are two regions on that circle that are highly variable.”

“What’s the advantage?”

“Mitochondrial DNA is present in hundreds to thousands of copies per cell, so it can be extracted from small or degraded samples where the genomic DNA is long gone. Researchers have found mitochondrial DNA in Egyptian mummies.”

“I doubt your septic tank was built by pharaohs.”

“I was trying to make this understandable.”

I thought of a better example.

“Mitochondrial DNA was used to determine that skeletons recently exhumed in Russia were those of Czar Nicholas and his family.”

“How?”

“Mitochondrial DNA is only passed on through maternal lines.”

“The whole shooting match comes from Mommy?”

“Sorry to break that to you, Ryan.”

“My gender knows grout.”

“The researchers compared DNA from the Russian bones to DNA obtained from living relatives, specifically Britain’s Prince Philip.”

“Queen Elizabeth’s hubby?”

“Prince Philip’s maternal grandmother was Czarina Alexandra’s sister, so Alexandra and her children, and Philip, inherited their mitochondrial DNA from the mother of both Alexandra and her sister.”

“Back to the cats.”

“Hair cells have no nuclei, so no genomic DNA. But mitochondrial DNA is present in hair shafts.”

“Gagné referred to epithelial cells.”

“Saliva, skin, buccal, vaginal. You might find saliva on cat hairs as a result of grooming—e-cells are also found in urine and feces. I appreciate Gagné’s pessimism about e-cells in this case.”

“Piss-poor chance of finding any.”

“According to Gagné, the mitochondrial sequences from the Specter cat were identical to those from the septic tank hair.”

“Meaning the Paraíso victim had contact with the Specter cat.”

“Yep.”

“And we know it wasn’t Chantale in that tank.”

“You’re right, Ryan. Cops are good at this.”

“The victim was someone who’d been to the Specter house, or at least been in contact with their cat.”

“Before last Christmas.”

He looked a question at me.

“That’s when Guimauve did a dead man’s float in the swimming pool.”

Ryan thought a moment, then, “I think little Chantale knows more then she’s letting on.”

“Someone does,” I agreed.

“Mrs. Specter?”

I shrugged.

Ryan and I locked eyes, each stuck on the same thought.

“I’ve never met the ambassador,” I said.

“Where is he?”

“Discussing soybean yields in Mexico City.”

“Odd, given his daughter’s recent bust.”

“Galiano said Specter delayed reporting Chantale’s disappearance. Once the cops were brought in, he wasn’t overly cooperative.”

“Kitty puts things in a whole new light.”

Lying just west of Centre-ville, Westmount flows down the mountain in a series of heavily shaded streets. Anathema to québécois separatists, the neighborhood is known for its high concentration of English speakers and its fierce federalist loyalty. Until the island of Montreal was reorganized, and many suburbs and outlying districts were incorporated under the Communauté Urbaine de Montréal umbrella, Westmount prided itself on its independence, low taxes, efficient management, and genteel good taste.

Westmount fought hard to prevent absorption into the new Super City. Upon losing, the citizenry drew their mink and cashmere coats about them, sniffed their affluent noses, and waited, confident that some resident lawyer would force a reversal on appeal.

They were still waiting.

Ryan exited the tunnel at Atwater, turned left on The Boulevard, turned right, and began climbing uphill. I watched the homes grow larger, imagined the expanding panorama of river and town as viewed from south-facing patios and sunrooms.

Westmount is like Hong Kong—the higher the elevation, the better the address. The Specter home was one of the largest in upper Westmount, a towering stone fortress, complete with turret, grille-work, and massive oak door. A cypress hedge prevented any view of the front of the property. That from the back must have been spectacular.

“Nice crib,” said Ryan, sliding to the curb.

“Mrs. Specter referred to it as a ‘little place.’”

“Arrogantly unpretentious. Very Westmount.”

“Mrs. Specter is from Charlevoix.”

Ryan thumbed the bell. Somewhere inside, chimes sounded.