Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Infertility And Sex Differentiation > Disorders of sexual development > Flashcards

Disorders of sexual development Flashcards

1
Q

Mechanism of Turner syndrome inheritance

A

Usually sporadic due to non dysjunction during meiosis

Increased risk if parent carries balanced rearrangement or maternal mosaic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Turner Indications prenatal

A

Abnormally high levels of human chorionic gonadotropin

Cystic hygroma ( excess fluid on nape of neck on scan)

Lymphadema - usually resolves if survives to term

IUGR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Turner Indications newborn

A

Small

Lymphadema ( hands and feet)

Nail hypoplasia

Excess skin at nape of neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Turner Indications childhood

A

Short stature

High arched palate

Short neck/ low hairline

Hypoplastic widely spaced nipples

Broad chest

Nail hypoplasia

Lymphadema

Prominent ears

Excess nevi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Turner Indications adolescence/adulthood

A

Short stature

Primary or secondary amenorrhea

Delayed puberty with no secondary sexual characteristics

Recurrent pregnancy loss in adulthood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the risk for Turners due to presence of Y chromosome material?

A

Those mosaic for a cell population with Y material have risk of gonadoblastoma in streak gonads (7-30%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cytogenetic X of Turner syndrome

A

~50% 45,X

~20% 46,X, abnormal X ( i(Xq) most common)

Remainder mosaic for 45,X and other cell lines (numerical or structural)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Characteristics of classical Turner syndrome

A

Congenital heart malformations (17-45%, no clear genotype- phenotype correlation), most commonly coarctation of aorta and bicuspid aortic valve

Structural kidney abnormalities 40% (single horseshoe)

Adult mean height 147cm

Streak ovaries

Infertile

No secondary sexual characteristics if untreated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Treatment of Turner syndrome

A

Growth hormone

Secondary sexual characteristics can be developed by treatment with oestrogen and progesterone at appropriate age

Fertility: egg donation

Removal of streak ovaries if Y chromosome material present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Features of numerical mosaics in Turner

A 
Milder phenotype
Maybe taller
May enter puberty spontaneously
More likely to have secondary amenorrhea or premature menopause
Maybe fertile or subfertile
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Features of structural mosaics in Turner syndrome

A

45,X and isochromosome, ring, or deletion of p or q arms

Milder phenotype

May only show short stature and gonadal dysgenesis

Presence of mitotically unstable structural abnormality of X results in post-zygotic generation of 45,X cell line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Turner Mosaics with markers

A

FISH to determine if marker is derivative of X or Y

Maybe elevated risk of gonadoblastoma if Y (critical region GBY, candidate gene TSPY)

Those X derived usually classic Turner phenotype

May have more severe phenotype if XIC absent (functional disomy) dependent on genes present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Incidence of Turner syndrome

A

1 in 2500-3000 live born girls

> 95% conceptuses fail to reach term

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Incidence of Klinefelter syndrome

A

1 in 500 to 1000 newborn males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Clinical features of Klinefelter syndrome

A

Taller than average with disproportionately long limbs

30-50% gynaecomastia (usually mild)

Infertile (azoospermia)

IQ lower than sibs

Most not detected until present with infertility

May have:
Small testes
Delayed or incomplete puberty
Reduced facial or body hair
Cryptorchism 
Hypospadias
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Klinefelter mosaics

A

Commonly found with normal cell line and less severely affected

17
Q

Inheritance of Klinefelter

A

Not inherited

Arises from non disjunction during meiosis in one parent

Mosaic forms occur due to abnormality in mitosis in early embryonic development

18
Q

Variants of Kleinfelter

A

Extra copies of the X 48,XXXY or 49,XXXXY

ID
Distinctive facial features (flat nose,epicanthic folds, prognathia)
Skeletal abnormalities
Poor coordination
Speech problems
19
Q

48,XXXX features

A
  • ID
  • Normal to tall height
  • Speech delay
  • Down syndrome like features including upward slanting paperback fissures, Microcephly, epicanthic folds, midface hypoplasia
  • menstrual disorders and reduced fertility
  • Additional X usually maternally derived
20
Q

SHOX micro deletion

A

SHOX= short stature homeobox gene

PAR1

Loss in Turner syndrome due to deletion causes short stature

Mutations cause Leri-Weill dyschondrosteosis

21
Q

Leri-Weill dyschondrosteosis

A

Autosomal dominant

Short stature

Abnormal wrist and forearm bones (curving) Madelung deformity

Muscle hypertrophy

High arched palate

More severe in females ( possible hormonal)

22
Q

Kallmann syndrome features

A

Anosmia due to a Genesis of the olfactory lobes

Hypogonadism secondary to deficiency in GnRH

Males may have micropensis and chryptorchism and fail to develop secondary sexual characteristics

Females fail to menstruate, little or no breast development

Mild ID

Colour blindness

23
Q

Forms of Kallmann syndrome

A

Autosomal dominant (loss of function of FGFR1)

Sex linked (mutation or deletion of KAL1 (ANOS1)) x linked recessive

24
Q

X linked icthyosis

A

1 in 2000-6000 males births

Scaling of skin, placental steroid sulphatase deficiency

Complete or partial deletion of STS gene Xp22.3

25
Q

Disorders of sexual development

A

Rare disorders in which there is a discordance between chromosomal, gonadal, and phenotypic sex.

A minority of patients receive a molecular diagnosis

26
Q

isodicentric Y

A

SRY present- male phenotype

No AZF: lack of spermatogenesis

27
Q

Y chromosome microdeletions

A

AZFa Complete absence of germ cells (sertoli cell only syndrome)

AZfb Arrest of maturation at spermatocyte

AZfc Variable- SCOS to oligozoospermia. Yq11.23 contains DAZ multigene family

28
Q

Myotonic dystrophy

A

Myotonia-cannot relax mucles
CUG repeat expansion

Male:

  • gonadal atrophy
  • reduced fertility

Female:

  • POF
  • higher miscarriage rate
  • obstetric problems (prematurity, faliure to progress)

cause of infertility not well understood

29
Q

Primary ciliary dyskinesia

A

Abnormal sperm motility

Around 50% males infertile

Females can be infertile due to impaired ciliary function in oviduct

30
Q

AD polycystic kidney disease (ADPKD)

A

Affects motility of spermatozoa

Infertility And Sex Differentiation (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions