This is a really interesting set of videos on how to make your own Solar Panels and Windmills to generate enough power to run your household.  Its pretty exciting stuff.
Click Here!  to see what I’m so excited about.  The more people do these types of things, the less toxic pollution goes into the atmosphere.
Our solar panel my son made is pretty cool and runs my refrigerator.   Just a suggestion in these tough economic and ecologically challeneged times.

Schizophrenia is a mental disorder where people who have it experience their thoughts as a process of hearing voices, including delusions, hallucinations, emotional indifference and social insensitivity as hallmarks of this disorder.   The disorder usually manifests itself in men in their late teens and early twenties, and in women in their twenties and thirties.  Statistical studies show us that schizophrenia affects approximately 2.4 million Americans

My cousin and her brother both suffer from the disorder.  Neither has had much luck with getting or maintaining a job, due to the fact that once a person gets on meds, they feel so good they feel like they don’t have to take them anymore.  And then, well, some pretty weird behavior ensues.

So is schizophrenia a genetically inherited trait?  And is there a gene or set of genes identified that are associated with the disorder? 

First, it is known that the disorder seems to run in families.  If a close relative has the disease, there is a higher probability that a person will develop it than in the general population.  One identical twin study showed that when one twin has schizophrenia, 68% of the time the other twin will have it too.  Another study showed an even higher association of 86% for identical twins.  But this will happen only 15% of the time with fraternal twins.   Even a first cousin having schizophrenia increases a person’s probability of having it from one to two percent.  (The general population shows a 1% chance association.) 

Current working theory is that there is a genetically inherited chemical imbalance in the brain that causes the strange thoughts, feelings and hallucinations.   Four specific genes have already been discovered that increase the risk of illness by influencing the level of a particular chemical that is crucial for communication among cells in the brain. This chemical is called glutamate.   

Most scientists agree that this is an organic disease, or a disease of development and really a disease of time.  It is clearly caused by something going wrong in the normal growth and development of the brain.   Growth is, of course, directed by genes.  But like most polygenic traits, these multiple genes react to each other, and to environmental factors, and to chance events. 

Interestingly, one of these chance events is postulated to be infection by the flu virus during gestation. In 1988 researcher Sarnoff Mednick was studying the medical records of children born to mothers who had aquired an infection with the influenza virus during pregnancy.  He was trying to explain a well known observation that more schizophrenics are born in the winter than in the summer.  This is true in both hemispheres of the Earth, even though there is a six month difference in the timing of the seasons.  This researcher’s hypothesis was that since flu epidemics usually happen in the winter, it is possible that there is something about a flu infection that causes the flu to have an effect upon the developing brain of the unborn child.  Records were examined from a well-documented flu outbreak in Helsinki in 1957.  He found that those who had been in the second trimester of their pregnancy during a flu infection were more likely to have schizophrenia than those who had been in the other trimeseters.   Influenza virions

So the working hypothesis is now that influenza infection in pregnancy causes some kind of damage to the developing brain of the fetus, which then predisposes the child to later psychosis.  This hypothesis involves the transactivation or transdeactivation of the flu virus proteins upon genes in the developing brain.

     A drawing of a kitty by a person with Schizophrenia.  (Source:  Flickr)

Some supporting evidence shows that monochorionic twins (share the same placenta and may develop in the same sac) and could encounter the same viruses as they also share the same fluid and circulating blood.  Researcher James Davis from Missouri, has found a much higher association for familia schizophrenia development between monochorionic vs. dichorionic twins.  

In 1984, a research study by Columbia University identified that approximately 14% of schizophrenia cases seem to have been caused by influenza during pregnancy.

The study indicated that Flu during the first trimester of pregnancy increased risk of developing schizophrenia in the child by approx. 700%, while flu during the third trimester increased schizophrenia risk for the child by 300%.

“This is the first time that this association has been shown using” blood tests that confirmed influenza infection during pregnancy, lead author Dr. Alan S. Brown, from Columbia University in New York, told Reuters Health. “It provides what I think is the strongest evidence to date linking (prenatal) influenza exposure with schizophrenia.”

Some experiments have supported the data above, while others only show a trend or nothing at all.  I think this is a facinating hypothesis, and hope to see more research results soon.

 References:  Wahlberg, K.E., et. al. 1997.  Gene-environment interaction in vulnerability to schizophrenia: Findings from the Finnish adoptive family study in schizophrenia.  American Journal of Psychiatry 154:355 - 62.

Mednick, S.A. et.al. 1988.  Adult schizophrenia following prenatal exposure to an influenza epidemic.  Archive of General Psychiatry  45:189-92

Davis, J.O.  et al.  1999.  Prenatal development of monozygotic twins and concordance for schizophrenia.  In the Nature-Nuture Debate. (eds. Ceci, S.J. and Williams, W.W.). Blackwell

Now and then as a high school teacher, I have to face facts and realize that it is once again time to step up and try to secure the funding that I need to teach an excellent class.  Now is one of those times. 

The State of Missouri has changed course curriculum requirements once again, and again districts like mine that operate on a shoestring are left scrambling for funding for the required lab and learning materials needed for our science classes.  This year, ecology has become a larger component of our biology classes, and we need some supplies and teaching aids to help our kids become proficient in this area.  To that end, I’ve published a project request at a website called Donors Choose.

onorsChoose.org is a simple way to provide students in need with resources that our public schools often lack. At this not-for-profit web site, teachers submit project proposals for materials or experiences their students need to learn. These ideas become classroom reality when concerned individuals, whom they call Citizen Philanthropists, choose projects to fund.

Proposals range from “Magical Math Centers” ($200) to “Big Book Bonanza” ($320), to “Cooking Across the Curriculum” ($1,100). Any individual can search such proposals by areas of interest, learn about classroom needs, and choose to fund the project(s) they find most compelling. In completing a project, donors receive student thank-you notes, classroom photos, and a teacher Impact Letter.

You can go to Donors Choose and search for my proposal “Make Our Students Eco-Smart” to see and read about it.  Please consider donating a few bucks, and please help me get the word out to others who may be interested in donating.  You can also click the link below to go directly to the proposal. 

Please consider helping us out, I feel my kids deserve the best I can offer to them.  Here is the link:

http://www.donorschoose.org/donors/proposal.html?id=263065&zone=0

I cannot imagine what a person with Osteogenesis Imperfecta (OI) must go through on a regular basis.  OI is also known as “Brittle Bone Disease” which is characterized by bones that break easily from little to no apparent cause.  The term “osteogenesis imperfecta” means imperfect bone formation.  The severity of the disorder varies, as a person may have just a few or as many as several  hundred bone fractures in their lifetime.  

According to the Osteogenesis Imperfecta Foundation (www.OIF.com), the disease affects an estimated 25,000 to 50,000 people in the United States.

There are actually a long list of symptoms for OI, brittle bones being one of many.  Folks with OI may have some or all of the following symptoms:

• Brittle bones
• Easily fracturing bone
• Low muscle mass
• In severe cases, late gestation or newly born babies may present with multiple fractures
• Joints are lax as are ligaments
• The sclera of the eye may be a blue to blue-grey color
• Thin skin
• Growth deficiencies
• Fragile and transparent teeth

A case: 

Pat Wilkerson, 70, said her husband could break a bone just turning over in bed. “It’s not that bad anymore, but he could,” she said.

She shared the story of a tough patch her husband went through last winter, when he developed a bad cold.

“He started coughing really bad, and he had all this pain in his back,” she said. “We didn’t know what was going on.”

A hospital staff was just as puzzled.

“Finally, they did a CAT scan and bone scan,” she said, “and found out he had three fractured vertebrae, just from coughing.”

A month later, he fractured another vertebra getting into his car. That’s when he learned his coughing had also caused him to fracture his ribs.

“I don’t know how he lived through it all, really,” Pat Wilkerson said. “It was really bad.”

There are eight different types of OI (I - VIII).  Type I is most commmon and is characterized by bone fractures during childhood and adolescence that often result from minor trauma.  One of the slightly more severe forms, type IV, is the other most common form.   Type II is the most severe, and involves an abnormally small, fragile rib cage and underdeveloped lungs. Infants with these abnormalities have life-threatening problems with breathing and often die shortly after birth.

One odd symptom of the disease is a blue color appearing in the whites or sclera of the eyes.  Here is a picture: 

Often, OI can be detected in utero as bones can be broken easily in some forms of OI due to kicking and movement of the fetus.  Look to the right to see an example of a broken fetal leg bone in OI. 

We know that there is a major role played by nature in OI.  The inheritance appears to be multigenic, or involves more than one gene.   The major issue in OI involves mutation of the gene for collagen, or mutation of a gene that produces an enzyme, like leprecan, that modifies collagen so it can fold properly and therefore become functional.  Many OI cases are born without the proper protein (collagen), or the ability to make it, usually because of a deficiency of Type-I collagen.  This deficiency arises from an amino acid substitution of glycine to cysteine in the collagen triple helix structure. The larger cysteine molecule creates sterical hindrance that creates a “bulge” in the collagen complex. Glycosylation of the cysteine molecule promotes further interference within the structure. As a result, the body responds by hydrolyzing the improper collagen structure. People with OI either have less collagen than normal or the quality is poorer than normal. As collagen is an important protein in bone structure, this impairment causes those with the condition to have weak or fragile bones.

Type VII, involving at least five mutations in the CRTAP gene, are responsible for a rare type of osteogenesis imperfecta. Several of these mutations prevent cells from producing any cartilage associated protein. Without this protein, bones and other connective tissues do not form properly, leading to a very severe form of the disorder. Another mutation in the CRTAP gene greatly reduces the amount of cartilage associated protein produced, which disrupts the normal formation of collagen. This genetic change causes less severe signs and symptoms of osteogenesis imperfecta.

Finally, the COL1A1 gene provides instructions for making part of a large molecule called type I collagen. Collagens are a family of proteins that strengthen and support many tissues in the body, including cartilage, bone, tendon, skin, and the white part of the eye (the sclera). Type I collagen is the most abundant form of collagen in the human body.

A list of the genes involved in OI can be found in the table below.

 Implicated Chromosomes:

1.  The LEPRE1 gene is on chromosome 1: base pairs 42,984,632 to 43,005,269.

2.  The CRTAP gene is on chromosome 3: base pairs 33,130,482 to 33,164,268

3.  The COL1A1 gene is on chromosome 17: base pairs 45,616,455 to 45,633,991

4.  The COL1A2 gene is on chromosome 7: base pairs 93,861,808 to 93,898,479

DNA tests for collagen mutations are available for OI I-IV by sequence analysis of the entire gene.  The tests are performed at six labs in various parts of the world.   There are also DNA tests using sequencing of the LEPRE1 and CRTAP genes.  All DNA tests can be performed on the fetus using CVS or amniocentesis.

Osteogenesis Imperfecta, like many genetic disorders, involves the mutation of one or more genes.  I can’t stress this enough to my students: most genetic disorders are usually due to mutation of more than one gene with mutations that can occur in multiple places on the gene. 

References:

Hi again to my readers.  I’ve been off the blog for awhile as I decided first semester after I had surgery was enough with teaching.  I felt I needed to take a break from many things.  But I’m back and happy to be picking up some of the fun stuff, like writing, that I missed while taking my break. 

My feet hurt.  Probably if I’d sit and teach instead of my hyperactive movements around the classroom, they wouldn’t feel so swollen at the end of the day.  I was sitting here thinking about this when I made an association (my brain is still functional at the end of the day, just not my feet) to a genetic disorder with an interesting name, Charcot-Marie-Tooth syndrome. 

With an unusual name, Charcot-Marie-Tooth is not an unusual disease.  The odd name comes from the three physicians, Jean-Martin Charcot, Pierre Marie, and Howard Henry Tooth who discovered and characterized the disease in 1886.   Charcot-Marie-Tooth disease is the most common inherited disorder that involves the peripheral nerves, affecting an estimated 150,000 people in the United States. It occurs in all races and ethnic groups. Worldwide, this disorder affects about 1 in 3,300 people.

CMT is a neuro-muscular degenerative disease where the affected individual slowly loses normal use of their feet, legs, hands and arms due to deterioration of peripheral nerves.   Peripheral nerves control movement by relaying impulses from the spinal cord to our muscles.   CMT is also referred as hereditary motor and sensory neuropathies (HMSN), and are a group of genetically heterogeneous diseases (meaning that CMT can arise by a variety of different mutations in different genes)  of the peripheral nervous system.  As nerves break down, the muscles become weakened due to the loss of stimulation of affected nerves.

The characteristic symptoms are 1.  Foot-Drop  Walking Gait, 2. Foot bone abnormalities, 3. High arches and hammertoes, 4. Problems with balance, 5. Problems with hand function, 6. Occasional lower leg and forearm muscle cramping, 7. Loss of some normal reflexes, 8. Scoliosis and 9. Breathing difficulties.

    CMT patients with foot bone abnormalities, including high arches.  

Hammertoes: 

At last count, there are multiple different mutations in multiple different genes on various chromosomes that can cause this disorder.   Type X CMT is caused by mutations in a gene on the X chromosome.  Type 1 CMT disease is characterized by abnormalities in myelin, the protective substance that covers nerve cells. Type 2 CMT is characterized by abnormalities in the fiber, or axon, that extends from a nerve cell and transmits nerve impulses. In intermediate forms of Charcot-Marie-Tooth disease, abnormalities occur in axons and myelin. Type 4 Charcot-Marie-Tooth disease affects either the axon or myelin. Types 1, 2, 4, and intermediate forms are further categorized by subtypes (such as 1A, 2A, 4A). Subtypes are distinguished by the specific gene that is altered. 

 One specific gene that produces CMT is the BSCL2 gene, which stands for Berardinelli-Seip congenital lipodystrophy type 2.  This mutation changes one of the protein building blocks (amino acids) used to make seipin. Specifically, the amino acid asparagine is replaced with the amino acid serine at protein position 88.  The mutation probably alters the structure of this protein with no known function, causing it to fold into an incorrect 3-dimensional shape. Research findings indicate that misfolded seipin proteins accumulate in the endoplasmic reticulum. This accumulation likely damages and kills motor neurons, which leads to muscle weakness in the arms and legs.    

Another gene, producing type 1B CMT produces “myelin protein zero” or MPZ.  MPZ is the gene’s official symbol. It produces a protein that is the most abundant protein in the myelin sheath, the covering that protects nerve axons and promotes the efficient transmission of nerve impulses. To understand this, think of myelin as a type of electrical tape.  Without the tape, electrical current can arc to other metals and not arrive at its appropriate destination. 

Specialized cells called Schwann cells are the only cells that make myelin protein zero. Schwann cells are part of the peripheral nervous system that connects the brain and spinal cord to muscles and to sensory cells that detect sensations such as touch, pain, heat, and sound. Myelin protein zero is required for the proper formation and maintenance of myelin. This protein acts like a molecular glue (adhesion molecule) and plays a role in tightly packing the myelin (myelin compaction).

From inside Schwann cells, myelin protein zero is inserted through the cell membrane, the structure that encloses a cell. One end of the protein remains inside the cell and is called the intracellular domain. The other end of the protein pokes through the membrane to the outside of the cell; this part of the protein is called the extracellular domain. The extracellular domain interacts with other substances that make up the myelin sheath. The section of myelin protein zero that spans the cell membrane is called the transmembrane domain.               Here is a gene map of MPZ.  

The MPZ gene is located on the long (q) arm of chromosome 1 at position 22.  More precisely, the MPZ gene is located from base pair 159,541,148 to base pair 159,546,367 on chromosome 1.

A third gene involves one type of kinesin, a microtubular motor that moves toward the positive end of microtubules.  Recall that microtubules are necessary for movement of cell organelles (they are like train tracks and the kinesins and dyneins are the engines) and cell division.  

Researchers have identified more than 100 MPZ mutations that cause a form of Charcot-Marie-Tooth known as type 1B. Many of these mutations alter the extracellular domain by replacing one of the building blocks (amino acids) in myelin protein zero with an incorrect amino acid. Other MPZ mutations lead to a protein that is missing one or more amino acids. The altered myelin protein zero probably cannot interact properly with other myelin components, which may disrupt the formation and maintenance of the myelin sheath. As a result, peripheral nerve cells cannot activate muscles used for movement or relay information from sensory cells back to the brain, causing the signs and symptoms of type 1B Charcot-Marie-Tooth disease.

A third gene involves one type of kinesin, a microtubular motor that moves toward the positive end of microtubules.  Recall that microtubules are necessary for movement of cell organelles (they are like train tracks and the kinesins and dyneins are the engines) and cell division.  The rapid transport of organelles, like vesicles and mitochondria, along the axons of neurons takes place along microtubules with their plus ends pointed toward the end of the axon.  Since the motors are kinesins, the CMT mutations that occur in this gene impair the ability of the nerve cell to communicate properly with the muscle.

Depending upon the mutation, and due to the fact that a variety of genes are involved, inheritance of CMT can occur in a variety of ways.  There is Autosomal Dominant inheritance, which produces the most common form of CMT.  There are also autosomal recessive and X-linked inheritance patterns.

With the number of various mutations producing the disease, we find a variety of presentations of the disease so there are many forms of the CMT disease. The severity of symptoms is quite variable in different patients and some people may never realize they have the disorder. CMT is not fatal and people with most forms of CMT have a normal life expectancy. 

References: 

 ”An Overview of Charcot-Marie-Tooth Disorders.”  Charcot-Marie-Tooth Association -CMTA.  http://www.charcot-marie-tooth.org

Godwin, Mike.  “File:Charcot-Marie-Tooth foot.jpg -Wikimedia Commons.” Wikimedia Commons.  20 Feb. 2009. 

Harris, Nick.  “Foot Clinic -A2FWiki.”  Ankle Foot Clinic - A2F Wiki.  20 Feb. 2009