Table of Contents
Is Klinefelter syndrome a dominant or recessive disorder?
Klinefelter syndrome with fabry disease–a case of nondisjunction of the X-chromosome with sex-linked recessive mutation. Heart Lung Circ. 2014 Dec;23(12):1149-52.
Is Klinefelter syndrome An example of Monosomy?
The exceptions to this are trisomy of chromosomes 13 (Patau syndrome), 18 (Edward syndrome), 21 (Down syndrome), X (XXY/Klinefelter syndrome or XXX), and Y (XYY); the only monosomy exception is the sex chromosomes (X0/Turner syndrome).
Is Klinefelter syndrome nondisjunction?
The classic form of Klinefelter syndrome is associated with a 47,XXY karyotype and is caused by meiotic nondisjunction of the sex chromosomes during gametogenesis (Fig.
What is the main genetic cause of Klinefelter syndrome?
Klinefelter syndrome is caused by an additional X chromosome. This chromosome carries extra copies of genes, which interfere with the development of the testicles and mean they produce less testosterone (male sex hormone) than usual.
Which type of chromosomal mutation causes Klinefelter syndrome?
Klinefelter syndrome is a sex chromosome disorder in boys and men that results from the presence of an extra X chromosome in cells. People typically have 46 chromosomes in each cell, two of which are the sex chromosomes. Females have two X chromosomes (46,XX), and males have one X and one Y chromosome (46,XY).
What is a monosomy disorder?
Monosomy refers to the condition in which only one chromosome from a pair is present in cells rather than the two copies usually found in diploid cells.
Is Cri-du-Chat recessive?
Most cases of cri-du-chat syndrome are not inherited. The deletion occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family.
What is genotype XXY?
Klinefelter syndrome is a genetic condition in which a boy is born with an extra X chromosome. Instead of the typical XY chromosomes in men, they have XXY, so this condition is sometimes called XXY syndrome. Men with Klinefelter usually don’t know they have it until they run into problems trying to have a child.
What causes Klinefelter syndrome nondisjunction?
However, because of nondisjunction, an egg cell or a sperm cell can also end up with an extra copy of the X chromosome. If an egg cell with an extra X chromosome (XX) is fertilized by a sperm cell with one Y chromosome, the resulting child will have Klinefelter syndrome.
What is Nullisomic and monosomic?
Nullisomy – the loss of both pairs of homologous chromosomes; individuals are called nullisomics and their chromosomal composition is 2N-2. Monosomy – the loss of a single chromosome; individuals are called monosomics and their chromosomal composition is 2N-1.
Is Xyy caused by nondisjunction?
47,XYY syndrome is not inherited. The chromosomal change occurs as a random event during the formation of sperm cells. An error in cell division called nondisjunction can result in sperm cells with an extra copy of the Y chromosome .
What is the origin of nondisjunction for an XXY genotype?
Most cases are caused by nondisjunction errors in paternal meiosis I. About eighty percent of individuals with this syndrome have one extra X chromosome resulting in the karyotype XXY.
What is Klinefelter syndrome?
Overview Klinefelter syndrome is a genetic condition that results when a boy is born with an extra copy of the X chromosome. Klinefelter syndrome is a genetic condition affecting males, and it often isn’t diagnosed until adulthood.
How many chromosomes are there in Klinefelter syndrome?
In Klinefelter syndrome, there are two X chromosomes and a Y chromosome (XXY). In rare cases, additional X chromosomes (XXXY or XXXXY) may also be linked to Klinefelter syndrome.
What is the prognosis for men with Klinefelter syndrome?
However, some men with an extra X chromosome have fathered healthy offspring, sometimes with the help of infertility specialists. Most men who have Klinefelter syndrome can expect to have a normal and productive life.
What are the possible complications of Kelly Klinefelter syndrome?
Klinefelter syndrome may increase the risk of: 1 Anxiety and depression. 2 Infertility and problems with sexual function. 3 Weak bones (osteoporosis). 4 Heart and blood vessel disease. 5 Breast cancer and certain other cancers. 6 (more items)