Turner Syndrome

Dr. Arvind Kumar

Introduction 

  • Turner’s Syndrome is a genetic condition that affects only females.

  • It occurs when one X chromosome is missing or partially missing.

  • This chromosomal abnormality affects growth, puberty, fertility, and multiple organs such as the heart, kidneys, and thyroid.

  • The condition is present from birth, though signs may appear at infancy, childhood, or adolescence.

  • Turner’s Syndrome happens randomly during cell division and is not caused by anything parents did.

  • With early diagnosis and proper medical care, most girls and women with Turner’s Syndrome can lead normal, healthy, and productive lives.

  • First described by Dr. Henry Turner in 1938, it remains one of the most common chromosomal disorders, affecting approximately 1 in 2,000–2,500 live female births.

What Is Turner’s Syndrome?

Turner’s Syndrome (also known as Monosomy X) is a chromosomal abnormality where a female is born with:

  • One missing X chromosome (45,X)

  • Or a structurally altered X chromosome

  • Or mosaicism (some cells are normal, others are missing an X)

Because the X chromosome carries important genes for growth, sexual development, and organ functioning, the condition leads to a characteristic set of physical and medical problems.

Types 

Understanding the genetic variations helps explain the differences in symptoms and severity.

1. Classic Monosomy X (45,X)

  • Complete loss of one X chromosome in all cells

  • Most severe form

  • Occurs in about 50% of cases

2. Mosaic Turner’s Syndrome (45,X/46,XX or others)

  • Some cells have monosomy X, others are normal

  • Milder symptoms; some women may menstruate or conceive

3. Structural Abnormalities of X Chromosome

  • Isochromosomes

  • Ring chromosomes

  • Deletions
    These cause variable clinical features depending on which part of the chromosome is missing.

 

Causes 

Turner’s Syndrome is not inherited in the vast majority of cases.
It occurs due to random nondisjunction, meaning:

  • There is an error during the formation of reproductive cells (sperm or egg).

  • One X chromosome fails to copy or separates incorrectly.

Key Point: Nothing the mother or father did causes Turner’s Syndrome.

Characteristic Features and Symptoms

Symptoms vary depending on the type and severity of chromosomal alteration.

Physical Features

  • Short stature (most common)

  • Webbed neck

  • Low hairline at the back of the head

  • Broad chest with widely spaced nipples

  • High-arched palate

  • Short 4th metacarpal

  • Lymphedema of hands and feet in newborns

  • Low-set ears

  • Narrow, upturned fingernails

Medical Problems and Organ Involvement

1. Cardiovascular Abnormalities

  • Coarctation of aorta

  • Bicuspid aortic valve

  • Hypertension

  • Risk of aortic dissection (important in adults)

2. Endocrine and Metabolic Issues

  • Hypothyroidism (often autoimmune)

  • Diabetes mellitus risk

  • Obesity tendency

  • Hyperlipidemia

3. Gonadal Dysgenesis

  • Streak ovaries

  • Ovarian failure

  • Absent or delayed puberty

  • Infertility

  • No menarche or irregular menses

4. Renal Abnormalities

  • Horseshoe kidney

  • Duplex collecting system

  • Increased risk of UTIs and hypertension

5. Skeletal Problems

  • Scoliosis

  • Osteoporosis due to estrogen deficiency

6. Ear and Hearing Problems

  • Recurrent otitis media in childhood

  • Sensorineural hearing loss in adulthood

7. Eye Problems

  • Strabismus

  • Ptosis

  • Refractive errors

8. Learning and Cognitive Profile

Most girls have normal intelligence, but may show:

  • Difficulty with spatial reasoning

  • Math difficulties

  • Non-verbal learning disability

  • Social anxiety

 

Diagnosis

1. Prenatal Diagnosis

  • Ultrasound findings: Cystic hygroma, fetal edema, congenital heart defect

  • Non-invasive prenatal testing (NIPT)

  • Chorionic villus sampling (CVS)

  • Amniocentesis

2. Postnatal Diagnosis

  • Short stature

  • Delayed puberty

  • Lymphedema

  • Cardiac anomalies

3. Confirmatory Test

🧬 Karyotyping is the gold standard.
It detects:

  • Monosomy X

  • Mosaicism

  • Structural abnormalities

Other tests:

  • FISH

  • Microarray

 

Treatment and Management

There is no cure, but early intervention helps ensure normal development and quality of life.

1. Growth Hormone Therapy

  • Started in early childhood

  • Increases adult height by 5–10 cm

  • Safe and widely recommended

2. Estrogen Replacement Therapy (ERT)

  • Begins around age 11–12

  • Induces puberty

  • Helps in bone development

  • Improves cardiovascular and metabolic health

3. Progesterone Therapy

  • Started after 1–2 years of estrogen treatment

  • Establishes menstrual cycles

4. Management of Infertility

Although most women are infertile, options include:

  • IVF with donor eggs

  • Cryopreservation (for those with mosaicism and residual ovarian function)

  • Gestational surrogacy

  • Strict cardiac evaluation before pregnancy due to high maternal risk

5. Cardiac Monitoring

  • Regular echocardiography

  • MRI of aorta

  • Blood pressure monitoring

6. Renal and Urinary System Care

  • Renal ultrasound

  • Monitoring hypertension

7. Hearing and ENT Evaluation

  • Yearly audiology tests

  • Early treatment for ear infections

8. Psychological and Behavioral Support

  • Counseling for social and emotional difficulties

  • Educational support for math or spatial learning difficulties

 

Complications Associated with Turner’s Syndrome

  • Infertility

  • Aortic dissection (life-threatening)

  • Osteoporosis

  • Hearing impairment

  • Hypertension and cardiovascular disease

  • Thyroid disorders

  • Obesity and diabetes

  • Psychosocial challenges

 

MCQs

1. Turner’s Syndrome is caused by:

A. Trisomy 21
B. Monosomy X
C. Trisomy 18
D. Triploidy

2. The most common karyotype in Turner’s Syndrome is:

A. 47,XXX
B. 45,X
C. 45,X/46,XY
D. 46,XX

3. Turner’s Syndrome affects which sex?

A. Male only
B. Female only
C. Both sexes
D. Neither

4. A newborn girl with puffy hands and feet most likely has:

A. Down syndrome
B. Turner’s syndrome
C. Patau syndrome
D. Edwards syndrome

5. Short stature in Turner’s syndrome is mainly due to deficiency of:

A. PTH gene
B. SHOX gene
C. FMR1 gene
D. SRY gene

6. The ovarian morphology typically seen in Turner’s Syndrome is:

A. Polycystic ovaries
B. Streak ovaries
C. Hyperplastic ovaries
D. Normal ovaries

7. The most common cardiac defect in Turner’s syndrome is:

A. Tetralogy of Fallot
B. Transposition
C. Bicuspid aortic valve
D. Atrial septal defect

8. A classic physical feature of Turner’s syndrome is:

A. Webbed neck
B. Simian crease
C. Brushfield spots
D. Microcephaly

9. Primary amenorrhea with normal pubic hair but absent breasts suggests:

A. Turner’s syndrome
B. Müllerian agenesis
C. PCOS
D. Kallmann syndrome

10. Girls with Turner’s syndrome typically have:

A. Tall stature
B. Short stature
C. Obesity always
D. Macroglossia

11. Which hormone is elevated in Turner’s Syndrome?

A. FSH
B. Estrogen
C. Progesterone
D. Testosterone

12. Most cases of Turner’s Syndrome arise due to errors in:

A. Meiosis
B. Mitosis
C. DNA repair
D. Transcription

13. Common renal anomaly seen in Turner’s Syndrome:

A. Horseshoe kidney
B. Polycystic kidney
C. Renal agenesis
D. Hydronephrosis only

14. Which diagnostic test is the gold standard?

A. Ultrasound
B. Karyotype analysis
C. FISH
D. NIPT

15. Turner’s Syndrome is associated with increased risk of:

A. Hypothyroidism
B. Hyperthyroidism
C. Cushing syndrome
D. Acromegaly

16. Hearing issues in Turner’s Syndrome are due to:

A. Sensorineural loss
B. Conductive loss
C. Both A and B
D. Central auditory loss

17. Intelligence in Turner’s Syndrome is usually:

A. Severely impaired
B. Normal
C. Borderline
D. Always low

18. Growth hormone therapy is started to improve:

A. Puberty onset
B. Height
C. Fertility
D. Cardiac function

19. Estrogen therapy should ideally start at:

A. 1–2 years
B. 5 years
C. 11–12 years
D. At menopause

20. Progesterone therapy is added after estrogen to:

A. Stop menstruation
B. Induce ovulation
C. Protect the endometrium
D. Treat acne

21. Spontaneous puberty is more common in:

A. Classic 45,X
B. Mosaic 45,X/46,XX
C. Ring chromosome
D. Isochromosome

22. Turner’s Syndrome increases risk of which metabolic disorder?

A. Addison disease
B. Diabetes mellitus
C. Nephrotic syndrome
D. Wilson disease

23. Which prenatal finding suggests Turner’s Syndrome?

A. Omphalocele
B. Cystic hygroma
C. Holoprosencephaly
D. Polydactyly

24. Most common cause of death in adults with Turner’s Syndrome:

A. Infection
B. Aortic dissection
C. Cancer
D. Renal failure

25. Turner’s Syndrome patients commonly have:

A. Normal uterus
B. Absent uterus
C. Rudimentary uterus
D. Double uterus

26. A typical lab finding in Turner’s Syndrome:

A. High estrogen
B. Low FSH
C. High FSH and LH
D. Low prolactin

27. The genetic condition is:

A. Always inherited
B. Sporadic, due to nondisjunction
C. Autosomal dominant
D. Autosomal recessive

28. Turner’s Syndrome is associated with which orthopedic condition?

A. Scoliosis
B. Genu varum
C. Hip dysplasia
D. Osteopetrosis

29. The neck webbing in Turner’s syndrome is due to:

A. Lymphatic obstruction
B. Muscle hypertrophy
C. Bone fusion
D. Neural tube defect

30. Pigmented nevi are:

A. Absent
B. Common
C. Diagnostic
D. Cancerous in 90%

31. Which chromosome is involved?

A. Chromosome 13
B. X chromosome
C. Y chromosome
D. Chromosome 21

32. Turner’s Syndrome can be detected in pregnancy via:

A. MRI
B. NIPT
C. Endoscopy
D. X-ray

33. Patients typically have which blood pressure pattern?

A. Low BP
B. Normal always
C. Hypertension risk
D. Shock

34. Turner’s Syndrome has increased risk of:

A. Osteoporosis
B. Hypercalcemia
C. Gout
D. Megaloblastic anemia

35. Which feature differentiates Turner’s from androgen insensitivity syndrome?

A. Short stature
B. Primary amenorrhea
C. Breast development
D. Female phenotype

36. Turner’s patients have:

A. Absence of pubic hair
B. Normal pubic hair
C. Excess pubic hair
D. Male pattern hair

37. Which screening is essential yearly?

A. Dental X-ray
B. Aortic imaging
C. EEG
D. Liver biopsy

38. Most Turner’s Syndrome individuals are:

A. Fertile naturally
B. Infertile
C. Fertile only at puberty
D. Fertile after GH therapy

39. Best fertility option for Turner’s Syndrome:

A. Natural conception
B. IVF with donor oocytes
C. Surrogate pregnancy only
D. No option exists

40. Which IQ domain is usually affected?

A. Verbal IQ
B. Spatial IQ
C. Writing skills
D. Memory

Answer Key

1-B
2-B
3-B
4-B
5-B
6-B
7-C
8-A
9-A
10-B
11-A
12-A
13-A
14-B
15-A
16-C
17-B
18-B
19-C
20-C
21-B
22-B
23-B
24-B
25-A
26-C
27-B
28-A
29-A
30-B
31-B
32-B
33-C
34-A
35-A
36-B
37-B
38-B
39-B
40-B