XYY syndrome
What is Jacob’s syndrome?
Jacob’s syndrome, also known as 47,XYY syndrome, is
a rare genetic condition that occurs in about 1 out of 1000 male children
. It belongs to a group of conditions known as “sex chromosome trisomies”, with Klinefelter’s syndrome being the more common type. This condition was initially discovered in the 1960s.
What are 2 disorders that only affect males?
Prostate cancer
and other diseases of the male reproductive system occur in men. Diseases of X-linked recessive inheritance, such as colour blindness, occur more frequently in men, and haemophilia A and B occur almost exclusively in men.
What are two genetic disorders that only affect females?
There are also two conditions that affect only females:
The Turner syndrome and the Rett syndrome
. The first one is a genetic disease which affects 1 out of 2.500 girls.
Which genetic disorders are more common in males than females?
Because females have two copies of the X chromosome and males have only one X chromosome,
X-linked recessive diseases
are more common among males than females.
What causes male only diseases?
This is why so many male-only diseases are attributable to
defective genes on the X chromosome
.” Such diseases include Duchenne muscular dystrophy, hemophilia and Hunter syndrome, which causes dwarfing, abnormal bones and mental retardation in males but usually does not affect females who carry the same mutated gene.
Why do some diseases only affect males?
X-linked recessive diseases most often occur in males. Males have only
one X chromosome
. A single recessive gene on that X chromosome will cause the disease. The Y chromosome is the other half of the XY gene pair in the male.
What is Metafemale syndrome?
From Wikipedia, the free encyclopedia. A metafemale (or superfemale) is
a low viability Drosophila fruit fly with a female phenotype in which the ratio of X chromosomes to sets of autosomes (A) exceeds 1.0
.
What is the karyotype for Turners syndrome?
Turner syndrome is sporadic. A majority of cases ascertained prenatally have a
45,X karyotype
. Paternal nondisjunction accounts for ∼70% of liveborn cases with a 45,X.
What is the male version of Turner syndrome?
Consequently, in the past,
Noonan syndrome
has been referred to as “male Turner syndrome,” “female pseudo-Turner syndrome,” or “Turner phenotype with normal chromosomes karyotype.” However, there are many important differences between the two disorders.
Can a boy have Turner syndrome?
Turner syndrome, characterized by the presence of a monosomy X cell line, is a common chromosomal dis- order. Patients with Turner syndrome are usually phenotypically female, and
male cases are rarely reported
.
Why does Turner syndrome only affect females?
Turner syndrome, a condition that affects only females, results
when one of the X chromosomes (sex chromosomes) is missing or partially missing
. Turner syndrome can cause a variety of medical and developmental problems, including short height, failure of the ovaries to develop and heart defects.
What is a super male?
Intelligence is usually in the normal range, although IQ is on average 10-15 points lower than siblings. In the past, there were many misconceptions about this disease. It was sometimes called the super-male disease because men with this syndrome were
thought to be overly-aggressive and lacking in empathy
.
What is Trisomy 23?
Humans have
23 pairs of chromosomes
. A trisomy is a chromosomal condition characterised by an additional chromosome. A person with a trisomy has 47 chromosomes instead of 46. Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy.
What causes Turner syndrome?
The cause of Turner syndrome is
a completely or partially missing X chromosome
. Turner syndrome symptoms include short stature and lack of breast development and periods. Treatment for Turner syndrome may include hormone therapy.
What is Turner mosaic syndrome?
Mosaic Turner syndrome (TS) is
a condition in which cells inside the same person have different chromosome packages
. Mosaic TS can affect any cell in the body. Some cells have X chromosomes and some don’t. Every 3 out of every 10 girls with TS will have some form of Mosaic TS.
