Ricki Lewis's Blog, page 45
July 24, 2016
Hannah Has Her Gene Therapy For GAN
Last week, 8 years and $8 million fund-raised dollars after the Sames family of Rexford, NY, began their battle against giant axonal neuropathy (GAN), their daughter Hannah finally received gene therapy.
JUST IN TIME
About 120 trillion viruses were injected into the fluid surrounding 12-year-old Hannah�s spinal cord, at the NIH Clinical Center. Each virus carries a working copy of the gene that encodes a protein called gigaxonin. When she awoke, the first thing Hannah said was "I'm hungry!" and soon after posted on Facebook, "I have an amazing family!" Indeed she does.
Although Hannah is the fifth child in the clinical trial, she�s the first whose body doesn�t make the protein at all, thanks to two deletion mutations. She required a separate protocol to suppress her immune system so that it would accept the treatment, which uses the harmless adeno-associated virus to deliver the genes. At one point, it seemed that the clinical trial wouldn't include her, despite the funding from Hannah's Hope Fund.
JUST IN TIME
About 120 trillion viruses were injected into the fluid surrounding 12-year-old Hannah�s spinal cord, at the NIH Clinical Center. Each virus carries a working copy of the gene that encodes a protein called gigaxonin. When she awoke, the first thing Hannah said was "I'm hungry!" and soon after posted on Facebook, "I have an amazing family!" Indeed she does.
Although Hannah is the fifth child in the clinical trial, she�s the first whose body doesn�t make the protein at all, thanks to two deletion mutations. She required a separate protocol to suppress her immune system so that it would accept the treatment, which uses the harmless adeno-associated virus to deliver the genes. At one point, it seemed that the clinical trial wouldn't include her, despite the funding from Hannah's Hope Fund.
July 8, 2016
Prostate and Colon Cancer News: The 2-Hit Hypothesis Revisited
A report and a case published in two major medical journals this week suggest that relatives of certain people with cancer may be at higher risk, due to inherited (germline) mutations in DNA repair genes.
Only 5 to 10 percent of cancers are inherited. Such individuals inherit a cancer-predisposing mutation in all their cells, and then a somatic (body) cell undergoes a second mutation that initiates the disease. The second mutation may be spontaneous or in response to an environmental factor such as smoking.
The one-two punch of inherited cancers, called the 2-hit hypothesis, was first described in 1971.
Only 5 to 10 percent of cancers are inherited. Such individuals inherit a cancer-predisposing mutation in all their cells, and then a somatic (body) cell undergoes a second mutation that initiates the disease. The second mutation may be spontaneous or in response to an environmental factor such as smoking.
The one-two punch of inherited cancers, called the 2-hit hypothesis, was first described in 1971.
June 28, 2016
African Ancestry and Dangerous Blood Clots
Inappropriate blood clotting can be a killer. Each year in the US, 300,000 to 900,000 people suffer a venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE). African Americans have a 30�60% higher incidence of either or both than people of European ancestry.
The risk factors that come up on the usual health websites for VTE tend to be the environmental ones that apply to everyone. But mention of genetic factors tend to be those found primarily among people of European ancestry � even though African Americans are at higher risk.
The risk factors that come up on the usual health websites for VTE tend to be the environmental ones that apply to everyone. But mention of genetic factors tend to be those found primarily among people of European ancestry � even though African Americans are at higher risk.
The Genetics of Nose-Picking
I�ve been bombarded lately with news releases reporting links between behavior and DNA.
In simpler times, genes encoded proteins, and the actions or absence of those proteins caused the trait or disease. But today, investigations from outside genetics � reported in psychology and politics journals, for example � are assigning genetic explanations to everything from liberalism to feelings about the death penalty to whether the sound of someone chewing is annoying.
Strange things can happen when non-geneticists publish genetics papers. So I thought I�d mention a few intriguing reports and propose a behavior to investigate: nose-picking.
In simpler times, genes encoded proteins, and the actions or absence of those proteins caused the trait or disease. But today, investigations from outside genetics � reported in psychology and politics journals, for example � are assigning genetic explanations to everything from liberalism to feelings about the death penalty to whether the sound of someone chewing is annoying.
Strange things can happen when non-geneticists publish genetics papers. So I thought I�d mention a few intriguing reports and propose a behavior to investigate: nose-picking.
June 6, 2016
My Husband�s Rare Cancer
�Genotyping isn�t standard of care, so we don�t do it,� said the surgeon dismissively to me a week ago, as if I�d asked him to bleed my husband or feel his head bumps.
Since the surgeon had just removed a foot of Larry�s colon, I stifled the urge to shout Gleevec! Avastin! Herceptin! I�d asked about testing the cancer cells for variants of well-studied oncogenes and tumor suppressor genes. The mutational state of tumor cells at the time of removal, especially given the rarity of the cancer�s origin � the appendix -- might prove informative should further treatment become necessary, even if that�s not for many years.
Since the surgeon had just removed a foot of Larry�s colon, I stifled the urge to shout Gleevec! Avastin! Herceptin! I�d asked about testing the cancer cells for variants of well-studied oncogenes and tumor suppressor genes. The mutational state of tumor cells at the time of removal, especially given the rarity of the cancer�s origin � the appendix -- might prove informative should further treatment become necessary, even if that�s not for many years.
May 24, 2016
Cow Embryos Reveal New Type of Chromosome Chimera
I�ve often wondered what happens between the time an egg is fertilized and the time the ball of cells that it becomes nestles into the uterine lining. It�s a period that we know very little about, a black box of developmental biology, because observing or doing anything to even the earliest human embryos is frowned upon.
Every time I write the following paragraph in new editions of my textbooks, I try to picture what can go wrong during those first cell divisions.
�The birth of a healthy baby is against the odds. Of every 100 eggs exposed to sperm, 84 are fertilized. Of these 84, 69 implant in the uterus, 42 survive one week or longer, 37 survive 6 weeks or longer, and only 31 are born alive. Of the fertilized ova that do not survive, about half have chromosomal abnormalities that cause problems too severe for development to proceed.�
Every time I write the following paragraph in new editions of my textbooks, I try to picture what can go wrong during those first cell divisions.
�The birth of a healthy baby is against the odds. Of every 100 eggs exposed to sperm, 84 are fertilized. Of these 84, 69 implant in the uterus, 42 survive one week or longer, 37 survive 6 weeks or longer, and only 31 are born alive. Of the fertilized ova that do not survive, about half have chromosomal abnormalities that cause problems too severe for development to proceed.�
Eliza Gets Her Gene Therapy!
Keeping a little girl at home for 722 days may seem cruel, but for the O�Neill family, it was a demonstration of astonishing bravery and love.
Glenn and Cara O�Neill had isolated their daughter Eliza to protect her from viral infection � which could have disqualified her from receiving gene therapy for Sanfilippo syndrome type A (aka mucopolysaccharidosis Type IIIA or MPS IIIA). Last week, she became patient #1 in Abeona Therapeutics' phase 1/2 clinical trial.
Glenn and Cara O�Neill had isolated their daughter Eliza to protect her from viral infection � which could have disqualified her from receiving gene therapy for Sanfilippo syndrome type A (aka mucopolysaccharidosis Type IIIA or MPS IIIA). Last week, she became patient #1 in Abeona Therapeutics' phase 1/2 clinical trial.
April 23, 2016
How Kevin Spacey is Altering Our Genes
Ridiculous headline? It�s just about as ridiculous as the one that circulated the Internet last week, parroting a genetically-ignorant news release from UCLA.
Here�s the headline, this one from Science Daily: �Fructose alters hundreds of brain genes, which can lead to a wide range of diseases.�
Imagine that. I can bite into a peach and jumpstart genetic chaos. I can give myself diseases with a frappuccino. Would a jolt of the high-fructose-corn-syrup variety kill me?
The good news is that apparently a diet rich in omega-3 fatty acids can reverse the rampant brain damage wrought by the evil sugar. The bad news is that the study was performed on 24 rats, counting the controls. And, of course, the science isn�t at all what the news release says it is.
Here�s the headline, this one from Science Daily: �Fructose alters hundreds of brain genes, which can lead to a wide range of diseases.�
Imagine that. I can bite into a peach and jumpstart genetic chaos. I can give myself diseases with a frappuccino. Would a jolt of the high-fructose-corn-syrup variety kill me?
The good news is that apparently a diet rich in omega-3 fatty acids can reverse the rampant brain damage wrought by the evil sugar. The bad news is that the study was performed on 24 rats, counting the controls. And, of course, the science isn�t at all what the news release says it is.
April 20, 2016
No Pain and Extreme Pain From One Gene
The family from northern Pakistan is one of the strangest to appear in the scientific literature. At its center is a 10-year-old, a street performer who walked on hot coals and inserted daggers through his arms before astonished crowds � feeling absolutely no pain. He died at age 13 from jumping off of a roof, considering himself impervious to all injury.
I�ve included this story in my textbooks for so long that I recently began to wonder if I�d been perpetuating an urban legend. Then a study in this week�s Science Translational Medicine led me back to the Pakistani boy. He was real. And it turns out that different mutations in the same gene can cause complete absence of pain, or attacks of pain so severe that sufferers compare the sensation to dipping one�s feet into hot lava. In these extremes lie clues to developing new painkillers.
I�ve included this story in my textbooks for so long that I recently began to wonder if I�d been perpetuating an urban legend. Then a study in this week�s Science Translational Medicine led me back to the Pakistani boy. He was real. And it turns out that different mutations in the same gene can cause complete absence of pain, or attacks of pain so severe that sufferers compare the sensation to dipping one�s feet into hot lava. In these extremes lie clues to developing new painkillers.
April 19, 2016
Redhead Gene Doubles Melanoma Risk, Without Sun
Variants of the melanocortin-1-receptor (MC1R) gene impart the red hair, fair skin, and freckles of a Prince Harry or Wilma Flintstone � and also poorer protection against ultraviolet (UV) radiation and therefore higher risk of developing skin cancers, including melanoma. But a new study published in
JAMA Dermatology
reveals that MC1R genotype alone more than doubles the risk of melanoma.
The Ginger Gene
Many colorful creatures owe their distinctive phenotypes to MC1R variants, from red pandas and ruffed lemurs, to Golden retrievers and brown cavefish and Kuzakh fat-rumped sheep. Orangutans are an exception � their hue arises from a different gene.
The Ginger Gene
Many colorful creatures owe their distinctive phenotypes to MC1R variants, from red pandas and ruffed lemurs, to Golden retrievers and brown cavefish and Kuzakh fat-rumped sheep. Orangutans are an exception � their hue arises from a different gene.
