Condition Lookup
Sub-Category:
Structural Chromosomal Abnormalities
Number of Conditions: 7
Cri-du-chat syndrome (5p deletion)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
high-pitched, cat-like cry in infants; intellectual disability; delayed development; microcephaly; distinct facial features (wide-set eyes, small jaw); low muscle tone (hypotonia); behavioral issues
Root Cause:
Deletion of a portion of the short arm of chromosome 5 (5p).
How it's Diagnosed: videos
Clinical examination, karyotyping, and FISH (fluorescence in situ hybridization) or array-based comparative genomic hybridization (array-CGH).
Treatment:
Symptom management through physical therapy, speech therapy, educational support, and behavioral interventions.
Medications:
No specific medications for the condition; treatments may involve antiepileptic drugs for seizures and medications to manage associated conditions such as ADHD or behavioral issues.
Prevalence:
How common the health condition is within a specific population.
Estimated at 1 in 15,000 to 50,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Most cases are de novo (new mutations); rarely, parental chromosomal rearrangements (e.g., balanced translocations) increase the risk.
Prognosis:
The expected outcome or course of the condition over time.
Lifelong condition with varying levels of intellectual and physical impairment; early intervention can improve quality of life.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Severe intellectual disability, speech difficulties, and potential organ system complications such as cardiac defects.
Wolf-Hirschhorn syndrome (4p deletion)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
distinctive facial features (greek helmet appearance); severe developmental delay; intellectual disability; seizures; poor growth; low muscle tone (hypotonia); congenital heart defects
Root Cause:
Deletion of a portion of the short arm of chromosome 4 (4p).
How it's Diagnosed: videos
Genetic testing including karyotyping, FISH, or array-CGH.
Treatment:
Multidisciplinary approach including physical therapy, anticonvulsants for seizures, and surgical correction of heart defects.
Medications:
Anticonvulsants like levetiracetam , valproic acid, or lamotrigine for managing seizures.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 50,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Mostly de novo deletions; rare cases involve parental balanced chromosomal translocations.
Prognosis:
The expected outcome or course of the condition over time.
Lifelong disability; severity varies; early intervention improves developmental outcomes.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Severe intellectual disability, epilepsy, and risk of recurrent respiratory infections.
22q11.2 deletion syndrome (DiGeorge syndrome)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
cardiac defects; immune system deficiencies; palatal abnormalities; hypocalcemia; learning disabilities; psychiatric disorders; distinctive facial features
Root Cause:
Deletion of a portion of chromosome 22q11.2.
How it's Diagnosed: videos
Genetic testing via FISH or microarray analysis; confirmed with clinical symptoms.
Treatment:
Management of specific symptoms including cardiac surgery, calcium supplements, speech therapy, and immune system support.
Medications:
Calcium and vitamin D supplements for hypocalcemia; antipsychotics or antidepressants for psychiatric symptoms.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 4,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Often de novo mutations; 10% are inherited from an affected parent.
Prognosis:
The expected outcome or course of the condition over time.
Variable; dependent on the severity of associated defects; early treatment improves outcomes.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Severe immune deficiency, cardiac complications, and increased risk for psychiatric disorders.
Williams syndrome (7q11.23 deletion)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
distinctive facial features; intellectual disability; overly social personality; cardiovascular issues (e.g., supravalvular aortic stenosis); growth delays; hypercalcemia
Root Cause:
Deletion of a region on chromosome 7q11.23.
How it's Diagnosed: videos
FISH or microarray analysis, alongside clinical evaluation.
Treatment:
Symptom management including cardiac surgery, dietary management for hypercalcemia, and educational support.
Medications:
Beta-blockers or antihypertensives for managing cardiovascular symptoms.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 7,500 to 10,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
De novo deletion in most cases; rare familial transmission.
Prognosis:
The expected outcome or course of the condition over time.
Variable; cardiac issues can be life-threatening; most individuals live into adulthood with proper care.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Cardiac complications, hypercalcemia, and behavioral issues.
Prader-Willi syndrome (15q deletion)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
hypotonia in infancy; poor feeding initially followed by hyperphagia; obesity; intellectual disability; behavioral issues; short stature; hypogonadism
Root Cause:
Loss of paternal genetic material in the 15q11-q13 region, commonly due to deletion or uniparental disomy (maternal inheritance of both copies).
How it's Diagnosed: videos
Methylation analysis and genetic testing to confirm deletion or uniparental disomy.
Treatment:
Management through growth hormone therapy, strict diet, physical activity, and behavioral therapy.
Medications:
Growth hormone to improve height and muscle tone; appetite suppressants or medications for behavioral problems may be considered.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 15,000 to 30,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Most cases are de novo mutations; recurrence risk for siblings is low unless familial chromosomal rearrangements are present.
Prognosis:
The expected outcome or course of the condition over time.
Lifelong condition; early intervention improves quality of life; obesity-related complications can affect life expectancy.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Severe obesity, type 2 diabetes, sleep apnea, and behavioral challenges.
Angelman syndrome (15q deletion or UBE3A mutation)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
severe intellectual disability; absent or minimal speech; ataxia; frequent laughter or smiling; seizures; microcephaly
Root Cause:
Loss of function of the maternally inherited UBE3A gene in the 15q11-q13 region, often due to deletion, mutation, or uniparental disomy.
How it's Diagnosed: videos
Methylation analysis, genetic testing for UBE3A mutations, or chromosomal microarray.
Treatment:
Symptom management through physical, occupational, and speech therapies; anticonvulsants for seizures.
Medications:
Anticonvulsants such as valproic acid, clonazepam , or levetiracetam for seizures.
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 12,000 to 20,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Usually de novo; rare familial cases involve inherited mutations.
Prognosis:
The expected outcome or course of the condition over time.
Lifelong condition; severe developmental challenges, but many individuals have a normal lifespan.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Epilepsy, sleep disturbances, and feeding difficulties.
Smith-Magenis syndrome (17p deletion)
Specialty: Genetics
Category: Chromosomal Disorders
Sub-category: Structural Chromosomal Abnormalities
Symptoms:
mild to moderate intellectual disability; behavioral problems (self-injury, aggression); sleep disturbances; distinctive facial features; speech and motor delays; obesity in adulthood
Root Cause:
Deletion of a portion of the short arm of chromosome 17 (17p11.2) or mutations in the RAI1 gene.
How it's Diagnosed: videos
Genetic testing using microarray analysis or targeted RAI1 gene sequencing.
Treatment:
Symptom-based management including behavioral therapy, melatonin for sleep regulation, and educational interventions.
Medications:
Melatonin or beta-blockers for sleep disturbances; medications for behavioral problems (e.g., risperidone or other antipsychotics).
Prevalence:
How common the health condition is within a specific population.
Approximately 1 in 15,000 to 25,000 live births.
Risk Factors:
Factors or behaviors that increase the likelihood of developing the condition.
Mostly de novo mutations or deletions; familial cases are extremely rare.
Prognosis:
The expected outcome or course of the condition over time.
Lifelong condition; early intervention improves developmental outcomes; obesity and sleep issues require ongoing management.
Complications:
Additional problems or conditions that may arise as a result of the original condition.
Behavioral issues, sleep disturbances, and obesity-related health problems.