Is angelman syndrome dominant or recessive and is it autosomal or sex-linked?
931359
Still studying the genetic link to angelman's syndrome.  From the research I have done, and who knows how much information on the internet is correct but I believe it is a sex-linked gene.
709683
Color blindness is a sex-linked thing (giggles from the 5th grader)\nThe gene is on the X chromosome.  Men get one X and one Y chromosome.  If their X has the gene for color blindness, there is no matching gene on the Y chromosome to "cover" for the defective gene.  The color blindness is expressed.\n\nWomen, however, are blessed with 2 X chromosomes.  If they get a gene for color blindness, the other X usually has a normal gene that can "do the work" that the abnormal gene cannot.  Color blindness is not expressed, and she is a carrier of the gene.\n\nWomen can be color blind if their color blind Dad marries a carrier Mom, and she gets 2 defective genes.\n\nHow's that?
992187
From your question, I'm guessing you already know that Barth Syndrome is an x-linked recessive disorder, which means it's caused by a mutation on the x-chromosome that shows up if you've got either two x-chromosomes with the mutation, or one x with the mutation, and one y chromosome.\n\nBarth Syndrome is caused by a mutation in the G4.5 tafazzn (TAZ) gene, which is located at Xq28 (which if you don't already know, specifies a paricular location on the x-chromosome).  The predicted protein sequence for the gene is 292 amino acids long, and has strong homology with (i.e. very similar to) a superclass of acyltransferases (a type of enzyme used in various cellular functions) that are highly conserved among different species.  There are over 50 different mutations of the TAZ gene that are associated with Barth Syndrom, of which 60% completely disrupt the function of the proteins, and another 30% change the charge of the protein.
177421
In 1993, Dr. Morris and collaborators discovered that Williams syndrome is the result of deletion of the elastin gene on one of the number 7 chromosomes. This deletion usually occurs sporadically. Individuals who have the deletion, however, have a 50% chance of passing that deletion on to their offspring.
559031
Well, it's a bit tough to draw in this text box, so how about a written description?  Willams Syndrome is an autosomal dominant deletion on chromosome 7, so essentially, the meiosis would have (in a heterozygous parent) two of the four resulting gametes with the WS trait, and two without.  The segregation is always independant, so the two affected ones could be any of the daughter cells.
583452
It's called Duchenne M.S. This is inherited as a sex-linked recessive trait. Most patients die by 20 years old. It's a progressive disease process.
489592
Nail Patella Syndrome (also called Fong's Disease, Hereditary Onycho-Osteodysplasia ['HOOD'] is characterized by several typical abnormalities of the arms and legs as well as kidney disease and glaucoma. It has been recognized as a hereditary condition for over 100 years and is inherited in an autosomal dominant manner. That is, the risk of transmission is 50% per pregnancy, irrespective of gender (just like flipping a coin). Approximately 20% of cases are sporadic, being the result of a new mutation. The incidence is approximately 1 in 50,000 and occurs throughout the world in all ethnic groups.\n\nThe below mentioned website should be very useful to you and give you 100% answers to all your queries on the subject.
62524
Ok, this sounds like a homework question so I'll give you some pointers.\n\n1) Color blindness (being a sex-linked trait) is recessive.\n2) So, the fact that they have a color blind kid means that the child is pure recessive so the mother must be a carrier.\nBased on this, a recessive father (cc) and a carrier mother (Cc) = work your Punnett square.
777180
ive tried looking, they wont reveal any of that. I do believe it is hereditary though
473864
Genotypes of man and woman : DdPp x DdPp\nPossible gametes of man and woman: DP Dp dP dp X DP Dp dP dp\nChildren: I guess its a dihybrid cross with 9:3:3:1 ratio of phenotypes since you have not mentioned the kind of inheritance.
687997
Causes\n \nX-linked recessive inheritanceThe fragile X syndrome is a genetic disorder caused by mutation of the FMR1 gene on the X chromosome. Mutation at that site is found in 1 out of about every 4000 males and 1 out of about every 6000 females.\n\nNormally, the FMR1 gene contains between 6 and 53 repeats of the CGG codon (trinucleotide repeats). In people with the fragile X syndrome, the FMR1 allele has over 230 repeats of this codon.\n\nExpansion of the CGG repeating codon to such a degree results in a methylation of that portion of the DNA, effectively silencing the expression of the FMR1 protein.\n\nThis methylation of the FMR1 locus in chromosome band Xq27.3 is believed to result in constriction and fragility of the X chromosome at that point, a phenomenon that gave the syndrome its name.\n\nMutation of the FMR1 gene leads to the transcriptional silencing of the fragile X-mental retardation protein, FMRP. In normal individuals, FMRP binds and facilitates the translation of a number of essential neuronal RNAs. In fragile X patients, however, these RNAs are not translated into proteins. The various sequelae of fragile X syndrome .\n\n[edit]\nTransmission of the Fragile X\nThe diagram (right) of X-linked recessive inheritance is not entirely inappropriate but it markedly oversimplifies the situation and does not provide a sufficient foundation for genetic counseling about the fragile X syndrome.\n\nBecause males normally have only one copy of the X chromosome, those males with significant trinucleotide expansion at the FMR1 locus are symptomatic. They are mentally retarded and may show various physical features of the fragile X syndrome.\n\nFemales have two X chromosomes and thus have double the chance of having a working FMR1 allele. Females carrying one X chromosome with an expanded FMR1 gene can have some signs and symptoms of the disorder or be normal.\n\nMales with the fragile X cannot transmit it to any of their sons (since males contribute a Y chromosome, not an X, to their male offspring.)\n\nFemales carrying one copy of the fragile X can transmit it to their sons or daughters. Sons who receive the fragile X are at high risk for mental retardation. Daughters who receive the fragile X may appear normal or they may be mentally retarded, usually to a lesser degree than boys with the syndrome.\n\nIt can begin at birth
617814
because it's a recessive sex linked gene carried on the x chromosome.  therefore, since men are XY, if the mother passes down the gene on her X chromosome, he will have colorblindness.  if the mom passes it on to a daughter, the father, who also contributes an X, will most likely have the dominant, normal sighted gene on it and the color blindness won't present itself.
722229
I am only a first year med student, but your topic interested me and I spent some time researching it.\n\nIt can also be called PNH (periventricular nodular heterotopia) or just PH. The most common form of the disease results from a mutation in a gene on the FLN-1 gene on the X chromosome.  What is odd is that it is a X-linked dominant mutation (most of what you hear with the X chromosome is recessive).  This means that either:\n\n-The mother of the child had it and passed it on\n-That a spontaneous mutation occured while the DNA of the egg was being copied.  (A baby girl who is born has already copied all the DNA for her future children, so it was nothing a mother could have affected through lifestyle)\n-A third option is that it is caused by something called "somatic mosaicism".  This is a difficult topic to explain.  It means that while the embryo was multipling and copying its DNA, a mutation occured in this gene just randomly.  Therefore every cell that comes afterward from this cell is also affected.  This means that if the mutation occured early, a lot of cells would be affected.  It it occured later in the embryo, less cells would be affected.  A 1999 article I read said that this was the generally accepted view on males with PH.   \nI also read that they generally see this disease in baby girls, because boys with the mutation rarely survive to term birth and are often miscarried.  Females have two X chromosomes and thus the other "normal" X chromosome must have some protective effect.  \nThe gene makes a protein that is important for the migration of neurons during embyrogenesis.  With this malfunctioning protein the neurons did not migrate properly during while in gestation (in the mother's womb).  \nI read a lot about epilepsy (seizures) being associated with PH (actually 80% according to two articles I read).\nI also read that the levels of mental retardation can be vary a lot (which is very much in line with the idea of somatic mosaicism = varying degrees of pathology depending on which types of cells have the mutation and which don't).  There are some reported to have no mental retardation.  \nI was not able to find any support groups for your son's condition which is critical for further information.  I would recommend that your son be seen by a pediatric neurologist if he has not seen on yet (though I would assume he has).\nFinally, I did find a web site that tries to confidentially try to link up families that have similar genetic conditions that there are no support groups for.  This issue is about Angelman's syndrome but if you go to the bottom of the "Links Line" there is a family with an 11 year old son with the condition that would like to talk to others.  There is a contact person at the bottom.\n\nhttp://www.geneticsupportcouncil.org.au/uploads/pdfs/Gene%20Advocate%20Edition%2026%20June%202004_364.pdf\n\nHope this all helps.  I am still an eager first year medical student and I have sympathy for your family since I have three daughters of my own.
290171
Super Male Syndrome is the XYY syndrome! \n\nXYY syndrome \n\nDefinition\nXYY syndrome is a chromosome disorder that affects males. Males with this disorder have an extra Y chromosome.\n\nDescription\nThe XYY syndrome was previously considered the super-male syndrome, in which men with this condition were thought to be overly aggressive and more likely to become criminals. These original stereotypes came about because several researchers in the 1960s found a high number of men with XYY syndrome in prisons and mental institutes. Based on these observations, men with XYY syndrome were labeled as overly aggressive and likely to be criminals.\n\nThese original observations did not consider that the majority of males with XYY syndrome were not in prisons or mental institutes. Since then, broader, less biased studies have been done on males with XYY syndrome. Though males with XYY syndrome may be taller than average and have an increased risk for learning difficulties, especially in reading and speech, they are not overly aggressive. Unfortunately, some text books and many people still believe the inaccurate stereotype of the supermale syndrome.\n\nGenetic profile\nChromosomes are structures in the cells that contain genes. Genes are responsible for instructing our bodies how to grow and develop. Usually, an individual has 46 chromosomes in his or her cells, or 23 pairs. The first 22 pairs are the same in males and females and the last pair, the sex chromosomes, consist of two X chromosomes in a female, and an X chromosome and an Y chromosome in a male.\n\nXYY syndrome occurs when an extra Y chromosome is present in the cells of an affected individual. People with XYY syndrome are always male. The error that causes the extra Y chromosome can occur in the fertilizing sperm or in the developing embryo.\n\nXYY is not considered an inherited condition. An inherited condition usually is one in which the mother and/or father has an alteration in a gene or chromosome that can be passed onto their children. Typically, in an inherited condition, there is an increased chance that the condition will reoccur. The risk of the condition reoccurring in another pregnancy is not increased above the general population incidence.\n\nDemographics\nXYY syndrome has an incidence of one in 1,000 newborn males. However, since many males with XYY syndrome look like other males without XYY syndrome, many males are never identified.\n\nSigns and symptoms\nThere are no physical abnormalities in most males with XYY syndrome. However, some males can have one or more of the follwing characteristics. Males who have XYY syndrome are usually normal in length at birth, but have rapid growth in childhood, typically averaging in the 75th percentile (taller than 75% of males their same age). Many males with XYY syndrome are not overly muscular, particularly in the chest and shoulders. Individuals with XYY syndrome often have difficulties with their coordination. As a result, they can appear to be awkward or clumsy. During their teenage years, males with XYY syndrome may develop severe acne that may need to be treated by a dermatologist.\n\nMen with XYY syndrome have normal, heterosexual function and most are fertile. However, numerous case reports of men with XYY syndrome presenting with infertility have been reported. Most males with XYY syndrome have normal hormones involved in their sperm production. However, a minority of males with XYY syndrome may have increased amounts of some hormones involved in sperm production. This may result in infertility due to inadequate sperm production. As of 2001, the true incidence of infertility in males with XYY syndrome is unknown.\n\nWhen XYY men make sperm, the extra Y chromosome is thought to be lost resulting in a normal number of sex chromosomes. As a result, men with XYY syndrome are not at an increased risk for fathering children with chromosome abnormalities. However, some men with XYY syndrome have been found to have more
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Is sex-linked. Sex linkage by definition involves all traits located on the sex chromosomes. Sex linkage doesn't mean that only males can be colour-blind, but it means that the sex of a child influences its chance to have that trait.\n\n(BTW "the" allele for colour blindness is crap... a normal human actually has 3 colour vision genes, two of these - "red" and "green" - on the X chromosome; meaning several types of colour blindness. A red or green can simply be left out when X chromosomes exchange DNA in egg cell formation, or you can have defective versions of either gene. As the third gene, that which codes for the blue receptor pigment, is located on another chromosome, there exists non-sex-linked colour blindness as well.)
214065
Downs syndrome is neither dominant nor recessive.  Nor has medical science been able to provide definitive answers as to what causes it..  It is commonly referred to as Trisomy 21 or Non-disjunction of the 21st chormosome.  Downs is a chormosome anomoly which occurs in very early stages of fetal development.  It is not, as is commonly believed, more prevalant in older women.  However age is believed to be a risk factor.  Almost all pregnancies today have a screening process from moms blood that can identify a risk factor.  The only definitive way to diagnose Downs during pregnancy is an  Amniocentisis..  After birth blood is taken and broken down to a level that a geneticist can observe the chromosomes.  \n\nThere is a whole lot more to know.  Most importantly, these children are a gift from GOD.  They are innocent and pure and loving.  My son is the greatest teacher I have ever known, my best friend (besides my wife), and my inspiration
349191
Just about everything we know about Bipolar Disorder in genetics is here: http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=125480 If the page looks somewhat scary and technical, just read what does make sense - and more than half the page is references, so don't get scared off. Oh, this is the NIH's (National Institutes of Health) OMIM or Online Mendelian Inheritance in Man webpage. All the research on human genetic disorders that's done is online, freely accessible by anyone, on this website, which is a wonderful thing if you think about it. Good luck with your research.