Turner syndrome is a chromosomal disorder in females resulting from the absence of one X chromosome, occurring in 1 in 2,000 to 2,500 live female births. It is characterized by symptoms like short stature, delayed puberty, and various physical anomalies, with a diagnosis confirmed through karyotype analysis. Treatment encompasses growth hormone therapy, estrogen replacement, and cardiovascular monitoring, with early intervention improving quality of life for affected individuals.

1. TURNER SYNDROME
HALA ESSAM MOHAMMED
ID : 431205462

2. GENERAL
INFORMATION
• Definition:Turner Syndrome is a
chromosomal disorder that affects
females, characterized by the partial or
complete absence of one X
chromosome.
• Incidence: Occurs in 1 in 2,000 to 2,500
live female births.
• Cause: Random error during cell
division leading to monosomy (45, X) or
mosaicism.
• Impact:Affects physical development
and reproductive health.

3. CASE STUDY
Patient:A 15-year-old
female presenting with
short stature and
delayed puberty.
History: No significant
medical history. Normal
developmental
milestones until age 10.
Symptoms: Lack of
breast development,
webbed neck, and
lymphedema at birth.
Family History: No
similar conditions
reported in family.

4. KARYOTYPE
FINDINGS
ASSOCIATED
WITH
TURNER
SYNDROME
• Prenatal.
• In roughly 1% to 2% of
conceptuses, the karyotype is
45,X. Ultrasound results for these
fetuses usually show nuchal
thickening or cystic hygroma. A
child with a normal phenotype is
born in the majority of cases
where mosaicism occurs between
a 45,X cell line and a cell line with a
second structurally normal sex
chromosome.4

5. CLINICAL
DESCRIPTI
ON
• Complete or partial absence of the second
sex chromosome and distinctive physical
characteristics are characteristics of Turner
syndrome. Short stature, ovarian failure,
edema of the hands or feet, nuchal folds, left-
sided cardiac abnormalities, low hairline, low
set ears, small mandible, cubitus valgus, nail
hypoplasia, hyperconvex nails, multiple
pigmented nevi, characteristic facies, short
fourth metacarpal, and high arched palate
are among the common phenotypic features,
though they can vary greatly. Turner
syndrome is typically not diagnosed in
females who are small in stature and have
deletions in the distal region of Xp, including
the SHOX gene. Similarly, early ovarian failure
is usually detected in people with Xq24
deletions who have primary or secondary
amenorrhea but are not short in stature

6. SPECIAL TESTING
CONSIDERATIONS
• In addition to karyotypic findings, phenotypic factors must be
considered in a differential diagnosis that includes Turner
syndrome. Since the phenotypic varies widely, a diagnosis cannot
be made until laboratory and clinical criteria have been taken into
account. Turner syndrome does not cause mental retardation. A
ring X chromosome with loss of XIST gene function and specific X-
autosome translocations are the only sex chromosomal structural
abnormalities that are likely to result in mental retardation.

7. PRENATAL DIAGNOSIS
• Sometimes a diagnosis is made while the fetus is still developing. Certain
characteristics on an ultrasound picture could make you suspect that your
unborn child has Turner syndrome or another genetic disorder that affects
fetal development.
• An elevated risk of Turner syndrome may also be indicated by prenatal
screening procedures that analyze the baby's DNA in the mother's blood
(prenatal cell-free fetal DNA screening or noninvasive prenatal screening). To
confirm the diagnosis, a karyotype should be performed either during
pregnancy or after birth.

8. DIAGNOSIS
• To rule out mosaicism and
diagnose Turner syndrome, a
standard 30-cell karyotype analysis
is necessary. The presence of a
45,X cell line or a cell line with the
short arm of the X chromosome
deleted (Xp deletion) confirms the
diagnosis.

9. DIAGNOSIS
• AY-centromeric probe should be used to check
for the presence ofY chromosomal material in
patients with Turner syndrome. Malignant
gonadoblastomas or testicular tissue may be
present in these patients.A comprehensive search
for gonadal, adrenal, or midline malignancies is
necessary when virilization is present.
• Individuals who have 45,X/46,XY mosaicism are at
a significant risk of developing gonadoblastoma and
may have mixed gonadal dysgenesis.To avoid dying
of cancer, these patients could need a preventive
gonadectomy.

10. DIAGNOS
IS
• PCR
• For detection of Y-chromosomal material
using PCR, a high rate of false-positive
results has been reported. Thus, caution
should be exercised in the interpretation
of Y-chromosome sequence PCR. FISH
confirmation using a Y centromere probe
after a positive PCR result is prudent.
• Genomic copy number microarray
studies can be used to further
characterize abnormalities that are
detected by cytogenetic studies.
However, microarrays may not detect
low-level mosaicism and should not be
used as the initial screen for sex
chromosome abnormalities.

11. METHODOLOGY OF MOLECULAR
BIOLOGY
Karyotyping: Standard
technique to detect
chromosomal
abnormalities.
Fluorescence In Situ
Hybridization (FISH):
Detects specific DNA
sequences for confirming
monosomy X.
PCR Analysis: Identifies
mosaicism or structural
abnormalities in the X
chromosome.
Next-Generation
Sequencing (NGS):
Provides a detailed
genomic analysis to rule
out additional mutations.

12. TESTS
HormonalTesting: Evaluates
estrogen and gonadotropin
levels (elevated FSH and LH).
Ultrasound:Assesses ovarian
development.
Echocardiography: Checks for
congenital heart defects, such
as coarctation of the aorta.
Bone Density Scan: Identifies
osteoporosis risk due to
estrogen deficiency.

13. TREATMENT
Growth Hormone Therapy:Administered to improve height
during childhood.
Estrogen Replacement Therapy (ERT): Initiated during
adolescence to induce puberty.
Cardiovascular Monitoring: Regular check-ups for heart
conditions.
Fertility Options:Assisted reproductive technologies like egg
donation for family planning.

14. CONCLUSION
• Turner Syndrome is a manageable condition with early
intervention and appropriate therapies.
• Advances in molecular biology provide robust diagnostic tools.
• Multidisciplinary care ensures better quality of life for individuals
with Turner Syndrome.

15. REFERENCES
• Gravholt, C. H., et al. (2017). Clinical
Practice Guidelines for Turner Syndrome.
Endocrine Society.
• National Organization for Rare Disorders
(NORD). (2022).Turner Syndrome
Overview.
• Sybert,V. P., & McCauley, E. (2004).Turner
Syndrome. New England Journal of
Medicine.
• American Society of Reproductive
Medicine. (2021). Fertility Options for
Turner Syndrome.

16. ThankYou