what type of sex chromosome abnormality is Cri du chat syndrome?
110282
Cri Du Chat isn't a sex chromosome abnormality - it's a deletion of the short arm (the upper part) of Chromosome 5 (a somatic chromosome, not an X or a Y that determines the sex of the individual).
743521
Aneuploidy is a condition in which the number of chromosomes is abnormal due to extra or missing chromosomes, in other words, it is a chromosomal state where the number of chromosomes is not a multiple of the haploid set. Normal diploid species have 2n chromosomes, where n is the number in the haploid set. Aneuploid individuals would have 2n-1 chromosomes (monosomy), 2n+1 chromosomes (trisomy), or some other such arrangement.\n\nA change in the number of chromosomes can lead to a chromosomal disorder. Aneuploidy is common in cancerous cells.\n\nMonosomy\nMonosomy is the presence of only one chromosome from a pair in a cell's nucleus. Partial monosomy occurs when only a portion of the chromosome has one copy, while the rest has two copies.\n\nHuman genetic disorders arising from monosomy are:\n\nX0-Only one X chromosome instead of the usual two (XX) seen in a normal female, also known as Turner syndrome \ncri du chat syndrome -- a partial monosomy caused by a deletion of the end of the short p (from the word petit, French for small) arm of chromosome 5 \n1p36 Deletion Syndrome -- a partial monosomy caused by a deletion at the end of the short p arm of chromosome 1 \n\nTrisomy\nA trisomy is the presence of three, instead of the normal two, chromosomes of a particular numbered type in an organism. Thus the presence of an extra chromosome 21 is called trisomy 21. Most trisomies, like most other abnormalities in chromosome number, result in distinctive birth defects. Many trisomies result in miscarriage or death at an early age.\n\nA partial trisomy occurs when part of an extra chromosome is attached to one of the other chromosomes, or if one of the chromosomes has two copies of part of its chromosome. A mosaic trisomy is a condition where extra chromosomal material exists in only some of the organism's cells.\n\nA trisomy can occur with any chromosome. Most trisomies result in spontaneous abortion; the most common types that survive to birth in humans are:\n\nTrisomy 21 (Down syndrome) \nTrisomy 18 (Edwards syndrome) \nTrisomy 13 (Patau syndrome) \nTrisomy 9 \nTrisomy 8 (Warkany syndrome 2) \nTrisomy 16 is the most common trisomy in humans, occurring in more than 1% of pregnancies. This condition, however, usually results in spontaneous miscarriage in the first trimester.\n\nTrisomy involving sex chromosomes in humans includes:\n\nXXX (Triple X syndrome) \nXXY (Klinefelter's syndrome) \nXYY (XYY syndrome) \n\nhope this helps
384876
it is a genetic disorder caused by having 3 chromosome #18s instead of 2. this is called trisomy 18. (down sydrome is caused by trisomy 21). \n\nover 90% of these babies have major heart defects. more than half are deaf. they require very intense care at birth, have a high risk of dying, and have major medical and developmental problems if they survive.
1072996
.\nThere will not be normal synapsis during zygotene of meiosis because one chromosome will not have a mate. A child may be born but the chances are that it will not be normal at all. Probably abort before birth. This is for a 47 chromosome male, and a 47 chromosome female, when the extra chromosome is an autosome.\n\nAn XXY is called a Klienfelter syndrome, sperms are usually not produced, breast development is common, voice tend to be higher pitched. The phenotype is male because of the y chromosome. Homosexuality is not mentioned.\n\nThe XXX female is sometimes fertile and can mate with a fertile XY male. There is a possibility that this female can mate with a XYY fertile male. This represents one of the few times a 47 female may mate with a 47 male and have normal children.
460679
XXY is called Klinefelter's Syndrome. Individuals with Klinefelter's are male instead of female, and they are almost always sterile.
594069
trisomy 18 or edwards syndrome, named after john edwards who first described the syndrome in 1960, is a genetic disorder caused by the presence of three, instead of two, chromosomes 18 in a fetus or baby's cells.\n\nthus being a genetic disorder, it is inherited. but its mode of inheritance cannot be explained using the punnett square or pedigree because it is a case of trisomy, or the presence of an extra chromosome.\n\nhowever, we can show that the edwards syndrome is inherited through the non-disjunction or improper separation of chromatids 18 at meiosis.\n\nwhere:\nchromosome 18 is represented by X\nn = 23, total human chromosomes in a germ cell\n(?) is an egg cell\n<?>- is a sperm cell\n\ntherefore,\nn - 1 = 22 or without chromosome 18\nn + 1 = 24 or with additional chromosome 18\n\ndiagram production of n+1 and n-1 gametes if non-disjunction occurs at:\na. meiosis 1\n(XX) -> (XX) (_) -> (X or n+1) (X or n+1) (_ or n-1) (_ or n-1)\nb. meiosis 2\n(XX) -> (X) (X) -> (/ or n) (&#92; or n) (_ or n-1) (X or n+1)\n\nnow, using gametes from meiosis 2:\n(&#92;) + </>- = 46 or normal\n(/) + <&#92;>- = 46 or normal\n(_) + </>- = 45 without chromosome 18 (non-viable)\n(X) + <&#92;>- = 47 with extra chromosome 18 or edwards syndrome\n----------------\n2 normal : 1 non-viable : 1 with edwards syndrome\n\ntry it using gametes from meiosis 1... ;p
548962
sounds like a genetic problem Hun..my uncles ex wife had the same with girl baby..was found to be  to do with chroma zones
1170133
This happens on occasion. My sister was told that her second and third child was a girl and both ended up being boys (Yeah since it was the first boys in family in 40 years). The only absolutely 100% test is an Amnio centisis. That is when they tast the fluid of the sack to see which chromosomes are there. But relax it happens. I hope this is what you were asking.
692190
Only if a genetically recessive trait runs in the family and both the guy and his sister have the defective chromosome, only then does the baby risk having a birth defect or mental retardation - even then(ie, with the defective recessive chromosome in both), the chance would be 1 abnormal child out of 4. If the guy and the sister have no such defective chromosomes, then the question of an abnormal/retarded child does not arise.\n\nIf, however, a genetically dominant trait runs in the family and either the guy or his sister have the defective chromosome, then the risk increases to 1 in 2  and if both have it, then the risk is 3 out of 4.\n\nIn any case, whether the baby will be normal or abnormal cannot be determined until a karyotyping of both the guy and his sis is done. Having said that, the rate of such disorders is quite low and in all probability, the child will be normal.
932994
Karyotype\n,\n\n Karyogram of human male using Giemsa staining.A karyotype is a standardized arrangement of all the chromosomes of a cell. In normal diploid organisms, autosomal chromosomes are present in two identical copies, although polyploid cells have multiple copies of chromosomes and haploid cells have single copies. The chromosomes are arranged and displayed (often on a photo) in a standard format known as an idiogram: in pairs, ordered by size and position of centromere for chromosomes of the same size. Karyotypes are used to study chromosomal aberrations, and may be used to determine other macroscopically visible aspects of an individual's genotype, such as sex. In order to be able to see the chromosomes and determine their size and internal pattern, they are chemically labelled with a dye ("stained"). The pattern of individual chromosomes is called chromosome banding, whereas the study of whole sets of chromosomes is known as karyology.\n\nNormal human karyotypes contain 22 pairs of autosomal chromosomes and one pair of sex chromosomes. Normal karyotypes for women contain two X chromosomes and are denoted 46,XX; men have both an X and a Y chromosome denoted 46,XY. However, some individuals have other karyotypes with added or missing sex chromosomes, including 47,XYY, 47,XXY, 47,XXX and 45,X. The karyotype 45,Y does not occur, as an embryo without an X chromosome cannot survive.
920293
gonosomes.    which are the sex chromosomes ! Hope this is it !! :o)
29588
A sex-linked trait is typically carried on the X chromosome, although it can also be carried on the Y-chromosome instead.  Common examples include color-blindness and hemophillia.
1027597
This could very well be normal.  Some people have an odd system that causes them to grow hair in odd places.  Some women have facial mustaches, or beards-look at grandma if you want better ideas.  \n\nThere is also a condition that IS known to medical science where the person has an extra cromosome.  I know I read about this one chick that didn't realize how awkward her situation was until about 30 or something.  She married a man (apparently she was a normal everyday woman) and then discovered she could not conceive.  Several tests later, she discovered she could not conceive because this woman was technically supossed to be a male at birth, but for some reason the testosterone did not develope at the proper stage of fetis growth, so the remaining estrogen production continued.  I think her Chromosome situation was XYX?  Where only two chromosomes are required for "normal" humans to determine sex, she somehow had both sides of the coin with a odd "mutation" of sorts if you will pardon the crude word.  (Imagine if you have a string of letters making a sentence so that it makes sense to read aloud--ie DNA/gene sequence coding- but then, as the chain of letters is being read loud, someone else had the ability to grab on the the last word of the sentence and gain improper context of the sentence-a possible enzyme or hormone that triggers on the last chromosome, in this case incorrectly as she had three instead of two)\n\nIt is also possible that as your body matures and grows with age, medication, and cell stimulation (whatever the cause of this cell stemulation is) might be manipulating your hormone production as it does with certain grandma's causeing odd things to happen to their bodies.  It is not uncommon.\nIf you are actually this worried about your gender, please...by all means see a doctor and validate your concerns with your doctor.  the Doc will definitely do what it takes to satisfy your curiousity, although I am certain it will end up costing quite a bit in lab tests and result confirmations.
224886
Don't ride this mom so hard for being concerned about her child's well being.  The fact that the pediatrician has ordered tests rather than offer reassurance says there may be something there.  Like any disease or syndrome, Turner's can present with a spectrum of severity.  There may be some other clues like widely spaced nipples or slight neck webbing in addition to short stature and delay of menarche, that is concerning the physician.  Turner's is an absence of the second sex chromosome, so the person has 45 chromosomes and is referred to as XO, with the O meaning absence of the second X chromosome.  They can live long and meaningful lives, but don't have the capability to reproduce.  There may be slight cognitive impairment or none at all.  Best wishes on this, but even if she has Turner's remember that there are lots of worse things she could be diagnosed with.
1046275
ABNORMALITIES IN CHROMOSOME STRUCTURE\n\nAbnormalities in chromosome structure follow a chromosome break and, during the repair process, the reunion of the wrong segments of the chromosome. If, following repair, there is a loss or gain of chromosomal material (an unbalanced rearrangement) there can be significant clinical consequences. If there is no loss or gain of chromosomal material (a balanced rearrangement), then the individual is mentally and physically normal. However, there is an increased risk of having chromosomally abnormal offspring because individuals who carry balanced chromosome rearrangements may produce chromosomally unbalanced gametes. \n\nTRANSLOCATIONS\n\nOf all the structural chromosome rearrangements, the most clinically significant is a translocation. Translocation involves two nonhomologous chromosomes (e.g., chromosome 2 and chromosome 6). Following a break in each of the chromosomes, and subsequent reunion, a segment of chromosome 2 becomes attached to chromosome 6 and vice versa. \n\n\nFig. 1.4. Translocation \n\nIn most cases, there is no loss or gain of chromosomal material during the exchange process. It is estimated that 1 in 500 individuals are normal translocation carriers.\n\nOn occasion, apparently balanced translocation carriers (on karyotype studies) are clinically abnormal. One explanation for this finding is that the break may have occurred in the middle of a gene which then results in the formation of an abnormally short, nonfunctional protein.\n\nIndividuals and families have been described with a translocation chromosome abnormality and a concurrent genetic condition; the genetic condition occurring because the chromosome breakpoint is in the midst of a gene. Research studies of these informative families have led to the localization of specific genes to specific chromosome segments (e.g., Duchenne muscular dystrophy on Xp21, neurofibromatosis on 17q, retinoblastoma on 13q14, etc.).\n\nWhen an apparently balanced translocation is found on amniocentesis, chromosome studies are done on both parents. If the translocation is familial (one of the parents is a normal translocation carrier), then it is safe to assume that the fetus carrying a similar translocation is going to be normal. If the translocation is de novo (the parents are not translocation carriers), then the fetus has a 10% empiric risk of having a possible genetic abnormality. It may seem surprising that the risk is not much greater. This is because only 10% of the genome (genetic constitution of an individual) carries coding sequences for genes. The other 90% of the genome consists of noncoding sequences. \n\nAs previously noted, people who carry balanced translocations have a high risk of miscarriages and abnormal offspring because they are more likely to create unbalanced gametes. In meiosis, the normal chromosomes and the translocated chromosomes pair up by creating a cross figure (quadrivalent) (Figure 1.5). The chromosomes are distributed to the daughter cells by the centromeres which are attached to spindle fibers. The spindle fibers contract and draw the attached chromosome to each of the poles (segregation). \n\nFig. 1.5. Balanced reciprocal translocation. This figure shows the generation of a balanced reciprocal translocation between chromosomes 2 and 6, and formation of a quadrivalent in meiosis: t = translocated segment, c = centric segment, solid circle = chromosome 2 centromere, open circle = chromosome 6 centromere. Homologous centromeres are both solid or both open circles and nonhomologus centromeres are one solid and one open circle (see text).\n\nThere are three ways the chromosome pairs segregate. Adjacent 1 segregation occurs when adjacent chromosomes with nonhomologous centromeres move to daughter cells. Adjacent 2 segregation occurs when adjacent chromosomes with homologous centromeres move to daughter cells. Alternate segregation occurs when alternate chromosomes with nonhomologous centromeres move to d
821644
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.)
308572
the female has 2 X chromasomes;\nthe male has 1 X and 1 Y chromasome; interestingly enough, it's the male who decides what gender a baby is going to be because either one X chromasome from the mother  joins with his one Y chromasome or his one X chromasome. It's kinda cool. ; )