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Monthly Archives: July 2010

Q&A: How Could My Sleuth Recognize a Chimera?

This will be the first post of a new series I’ll add to the blog from time to time. I get cool questions from writers all the time so I thought it might be fun to post some of the most interesting ones here.


Back in 2004, I received a question about chimerism from Susanna Shaphren. I included it in my book FORENSICS & FICTION. I thought it might help readers understand this fascinating medical condition a little better so here it is:

Q: My question is about chimeras, individuals whose body is made up of two genetically different lines of cells. The case I read about involved a woman who underwent tests to determine if one of her sons was suitable as a kidney donor for her.  Testing determined that two of her sons were NOT her biological children. Their DNA came from the mother’s twin, who instead of surviving to be born was somehow absorbed into the birth mother’s body.

I would love to use this as a springboard for fiction, but I need some help to be sure I’m on at least semisolid ground. Unless the character with this condition needed an organ transplant, would there be any other possible way for the condition to be diagnosed?

Susanne Shaphren
Phoenix, Arizona
Author of “Arrangements,” in Mystery Writers of America Presents Shoe Business Is Murder and “The Best of Friends,” in Sex, Lies, & Private Eyes

A: When an egg and a sperm join to make a fertilized egg, the genetic makeup of the offspring is set at that moment. Normally the cell will divide into two, and those into four, and those into eight, and so on. At some point in the growth of the zygote the cells begin to specialize or what we call differentiate. Some will become brain tissue, others blood cells, and others muscle cells.

In fraternal twins two eggs are fertilized by two sperm and this process occurs in parallel, and two entirely distinct individuals result. In identical twins the original fertilized cell (egg) divides into two cells, but these two drift apart, and then each proceeds along the growth path in tandem. This creates two individual with identical genetics. After all, they started from the same cell and thus from the same egg and sperm. So far so good.

In chimeras fraternal twins are formed (two eggs and two sperm, and two genetically different individuals) but these two original cells (fertilized eggs) stick together. As growth takes place the developing zygote is composed of two distinctively different cell types with two distinctively different genetic make-ups. As these cells begin to specialize, some organs and tissues may come from one type of cell and some from the other, and still others may develop with a mixture of cell types. This leads to a chimera, where various body tissues (liver, blood, skin, heart, brain) may have one or the other or both of the two original DNA profiles. This can lead to confusion in any testing dependent upon DNA typing.

Chimeras may appear normal or may display certain mosaic patterns, particularly unusual pigmentation patterns, on their skin. This is merely an expression of their two genetic types. A mosaic in art is something made up of different-appearing distinct pieces. The same holds true here, since the cells of the person contain separate and distinctive DNA patterns.

If the person were normal in appearance, the only time a chimeric condition would be diagnosed would be if DNA testing were undertaken. This is done in organ transplantation, paternity testing, and in criminal situations, to name a few circumstances. Otherwise the person may never know of his condition.

If your character displayed an odd mosaic skin pattern, your sleuth could see this and suspect that the person was chimeric. These skin patterns can be almost anything, even areas of a distinct checkerboard pattern.

 
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Posted by on July 5, 2010 in DNA, Medical Issues, Q&A

 

Tess Gerritsen, Jane Rizzoli, and Maura Isles get ICE COLD

Tess Gerritsen is the best-selling author of the Jane Rizzoli and Maura Isles novels. She has an extremely loyal following for one simple reason: Tess writes great books. The latest is titled ICE COLD, and like its predecessors will certainly be a bestseller. But there is even bigger news from Tess: Rizzoli & Isles is a new TV series coming to TNT on July 12th.

To discuss her new book and TV series, Tess graciously agreed to answer a few question for The Writer’s Forensics Blog.

Tess, welcome.

DPL: Wow. Jane Rizzoli and Maura Isles make it to the screen. How did that come about? Was it your idea or did the studio come to you?

TG: About three years ago, my characters were optioned by producer Bill Haber at Ostar Enterprises.  Since I’ve had my books optioned or bought outright several times, and nothing ever came of it, I did not let myself get too excited by this particular option deal.  I signed the contract, cashed the check, and went back to writing my books.  A year later, after the option ran out, Haber renewed the option.  That was nice, but again, I didn’t let myself get too excited, even though Haber called me several times to express his continuing commitment to turn my books into a TV series.  Then last year, after he hired Janet Tamaro to write the pilot, things began to happen quickly.  The script came in, and everyone loved it.  TNT issued a “talent-contingent” order for a pilot.  A few weeks later, Angie Harmon signed on to play Jane Rizzoli, and the rest of the cast fell into place.  The pilot was filmed, and a month later, TNT ordered ten episodes.  Once the ball started rolling, it just picked up speed.  I certainly never expected it to reach this point!

DPL: I assume you will serve as consultant for the new series. True? Will you write some of the scripts?

TG: I won’t be writing any of the scripts.  For that, they have a terrific team of six writers, and they are crafting all the episodes.  Every so often, they’ll shoot me an email asking for suggestions on a particular plot issue, but other than that, they are the ones writing this show.  And I’m very happy that they’re using so much from the books.

DPL: Will Rizzoli and Isles change in any way for the TV series or will they hold true to the novels?

TG: Their personalities are very true to the books.  Jane is still the tough, aggressive, blue-collar cop.  Maura is still the elegant and logical “Mr. Spock” scientist.  The biggest change is in their physical appearance.  Angie is far more attractive than Jane, and Maura Isles is now a blonde (perhaps to contrast with Jane.)  But when it comes to the way they behave and think, they are definitely my characters.

DPL: When does the series debut? How many episodes can we expect in the first season?

TG: “Rizzoli & Isles” will debut on TNT July 12 at 10 PM  (9 CT).  TNT has ordered 10 episodes.

DPL: Without giving too much away, can you tell us a little about the first episode?

TG: The plot is based on my book THE APPRENTICE, which is the second book in the Rizzoli series.  It introduces all the major characters and sets the foundation for their relationships.

DPL: As the series unfolds, will we see any major changes in either Jane or Maura or in their relationship?

TG: Jane and Maura are much closer to being real friends in the TV series than they are in the books, where their relationship is a bit more distant and wary.  The show plays up the contrasts a bit more too, with Jane being more tomboyish and Maura being more girly.  There’s a great deal more humor in the TV show, and the interplay between the two gals had me laughing out loud when I watched the pilot — this despite the plot was about a gruesome serial killer.

DPL: Your latest book in this series is ICE COLD. By my count that will be the 8th novel in the series. Can you tell us a little about this story?

TG: Yes, it’s the 8th book in the series.  I take Maura out of Boston for this tale.  She heads to Wyoming for a medical conference, and takes a spur of the moment ski trip with some friends.  A snowstorm, and misplaced faith in their GPS, sends them up a mountain road where they become stranded and must seek shelter in a remote little village called Kingdom Come.  There they find abandoned houses, meals still on tables, and dead house pets.  What happened to the inhabitants?  That mystery — and their ever more disastrous attempts to reach safety — send Maura on a harrowing adventure.

Visit Tess’s Website

 
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Posted by on July 2, 2010 in Interviews, Writing

 
 
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