Ricki Lewis

In a list of famous genes, RB1 would probably be #1. It’s the tumor suppressor gene whose “loss of function” is behind the childhood eye cancer retinoblastoma, and that Alfred Knudson investigated to deduce the 2-hit mechanism of cancer.

In 1971, the idea that the normal function of a gene could be to prevent cancer was revolutionary. Now a study in Lancet Oncology finds that an amplified oncogene can cause the eye cancer too, with just one “hit.” Read More 

Since my January 24 blog “My Cat Has AIDS," about my two feline immunodeficiency virus (FIV)-positive cats, we’ve acquired a third, the handsome Romeo. He, too, came to us from Orange Street Cats, on Valentine’s Day.

Romeo was found in an inner city park where people who can barely afford to feed their families nevertheless care for the burgeoning population of stray cats. “His origins are unknown, but I’d been feeding him along with other backyard cats where I live, a short distance from the vet,” said Ethel, the kind woman who saved him. “When Romeo injured his front leg, I trapped him and took him to the vet. The leg wasn't broken, but they determined he is FIV positive, with no symptoms, so I couldn't keep him,” because she already had an adult, indoor cat. Read More 

While we’re busy debating the pros and cons of clinical genome sequencing and tossing around buzzwords like “personalized” and “translational” medicine, I’ve recently caught some health care providers ignoring the archaic skills of communication and common sense. So while we await genome analysis apps and DNA annotators in our doctors’ offices, here are 3 suggestions on how to provide personalized medicine right now:

1. Read the patient’s chart (paper or digital)

2. Listen to the patient

3. Look at the patient

Disclaimer: Today’s blog is anecdotal and non-scientific, but may identify a trend.
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“When you hear hoofbeats, think horses, not zebras.”

Every doctor-to-be hears this mantra. Rare Disease Day, February 28, celebrates the 7,000 or so diseases that are zebras, each affecting fewer than 200,000 people.

Giant axonal neuropathy (GAN) isn’t a zebra, but a unicorn. Eight-year-old Hannah Sames inherited one mutation from each of her parents in a gene that encodes a protein called gigaxonin. As a result, the axons of her motor neurons are slowly filling up with haphazardly-arrayed intermediate filaments. The cells bulge, blocking the messages to her muscles. She’s one of only 50 in the world known to have GAN. But if all goes according to schedule, Hannah and several other youngsters are going to have gene therapy to correct the disease. Read about it at Hannah’s Hope Fund.

Two years ago, at the annual meeting of the American Society of Gene and Cell Therapy in Washington, I had the honor of watching Hannah’s marvelous mom Lori as she watched a child helped by gene therapy – Corey Haas, whose story bookends a brief history of the technology in "The Forever Fix: Gene Therapy and the Boy Who Saved It".

Here’s an excerpt, for Rare Disease Day. Read More 

Exomes are big news. Sequencing of the protein-encoding part of the genome is increasingly solving medical mysteries in children. It began with Nicholas Volker and his recovery from a devastating gastrointestinal disease with a stem cell transplant once his exome sequence revealed his problem. And recent Medscape assignments reveal the trend: 7 of 12 kids’ exomes leading to diagnosis at
Duke University
from May 10, 2012; whole genomes of 5 infants from the neonatal intensive care unit at Children’s Mercy Hospital and Clinics in Kansas City, Missouri from October 3, in under 2 days each, focusing on 600 single-gene diseases; and 300 patients at the Whole Genome Laboratory at the Baylor College of Medicine, with 300 more waiting -- 85% of them kids, from November 9, 2012. (You have to sign in to Medscape; it’s free.)

But wait.

Before we all run out to get our exomes and/or genomes sequenced, Read More 

In the usual trajectory of passing on genetic information, the older tell the younger, when the time is right. Typically, a patient has a genetic test because family history, ethnic group, or some other clue suggests to an astute practitioner an increased risk of something specific.

If a test reveals a mutation that could cause a disease, then the patient and perhaps her partner discuss how, when and what to tell their children – in the best of circumstances, with the help of a genetic counselor. Read More 

I am astonished, once again, by the complexity and unpredictability of science.

Last week, a paper in the Proceedings of the National Academy of Sciences (PNAS) reported that gene therapy to treat a form of blindness called Leber congenital amaurosis type 2 (LCA2) doesn’t stop degeneration of the rods and cones – the photoreceptor cells that provide vision. Gene therapy sends the genetic instructions for a protein called RPE65 into a layer of cells that supports the rods and cones – the retinal pigment epithelium, or RPE. The protein is essential for the eye to use vitamin A. And the gene therapy works, so far.  Read More 

Juice was an impulse buy.

It was early July 2003, and we were headed to the mall for a gift for Carly, about to turn 15. We parked near a bus equipped as an animal shelter.

Inside, kitten-filled cages lined the walls, except for one, which had a large, orange and white cat stuffed into it. Carly made a beeline for him and the attendant hoisted him out and handed him over. I reminded Carly that we already had 5 felines, but we knew he’d be left behind as the kittens were adopted.  Read More 

More than a decade before Sally Temple, PhD, and her husband Jeffrey Stern, MD, PhD, discovered stem cells in human eyes, they suspected the cells would be there. They knew it from the salamanders.

A SPECIAL FONDNESS FOR AMPHIBIANS
When William Shakespeare included “eye of newt” ingredients of the Three Witches’ brew in Macbeth, he probably knew what he was doing. Dr. Temple, who grew up in northern England, said it’s long been common knowledge there that newts can regrow their parts. In the late 1800s, biologists began to study regeneration in salamanders.

By the 1950s, embryologists had discovered that certain amphibian eyes regenerate thanks to a single layer of cells, called the retinal pigment epithelium (RPE), which hugs the photoreceptors (the rods and cones).  Read More 

My immune system is still on hyperdrive from what may have been the flu three weeks ago. I qualify my self-diagnosis because I never had a test to tell whether viruses or bacteria had invaded my body.

I’ve long wondered why such diagnostics aren’t, by now, in routine use. Molecular biology was pioneered on the genetic details of bacteria and their viruses in the 1970s, and by now most of our pathogens have had their genomes sequenced.  Read More