CMA - Postnatal

Chromosomal Microarray (CMA) has become a key diagnostic tool for postnatal genetic evaluation, providing unparalleled insights into genetic abnormalities that impact developmental and health outcomes in children. A growing body of clinical evidence supports CMA as a first-line genetic test for individuals presenting with developmental delays, intellectual disabilities, autism spectrum disorders, and multiple congenital anomalies. As an advanced, high-resolution genetic test, CMA is quickly replacing traditional karyotyping in the diagnosis of chromosomal anomalies and related genetic conditions.

CMA postnatal testing is highly recommended for children and individuals with developmental delays, intellectual disabilities, congenital anomalies, and unexplained clinical presentations that may have a genetic basis. It is also invaluable for identifying chromosomal abnormalities that could not be detected through traditional karyotyping or other genetic tests.

Unlike other tests, CMA also screens for regions of the genome affected by uniparental disomy (UPD), a condition where a child inherits both copies of a chromosome from one parent, which can result in developmental and metabolic issues.

Clinical Utility of CMA - Postnatal

1. Diagnosis of Genetic Conditions: CMA is essential for diagnosing various genetic conditions, including those involving intellectual disability, developmental delays, and congenital anomalies.

2. Differentiating De Novo vs. Familial Disorders: CMA helps distinguish between de novo (new, spontaneous mutations) and inherited chromosomal anomalies, providing families with valuable information about recurrence risks.

3. Clarifying Clinical Significance of CNVs: CMA aids in interpreting the clinical relevance of CNVs, which can influence patient management strategies.

4. Tailoring Treatment and Management: By understanding the specific chromosomal changes causing a condition, doctors can tailor treatment plans and provide families with more accurate prognoses.
   
   

When to Consider CMA Testing - Postnatal

CMA is recommended in a wide range of postnatal scenarios, including:

1. Developmental Delays and Intellectual Disabilities: Children with unexplained developmental delays or intellectual disabilities can benefit from CMA testing to identify underlying genetic causes.

2. Multiple Congenital Anomalies: Infants born with multiple congenital anomalies, especially when the anomalies do not fit a well-known syndrome, should undergo CMA testing to identify chromosomal imbalances.

3. Autism Spectrum Disorders: For children diagnosed with autism or pervasive developmental disorders, CMA can help uncover the genetic causes and offer personalized intervention strategies.

4. Unexplained Physical or Developmental Features: CMA is useful for children with ambiguous genitalia, facial dysmorphisms, or limb anomalies, helping to explain the genetic basis of these features.

5. Seizures and Neurological Conditions: Children with epilepsy or neurological abnormalities can benefit from CMA to detect genetic changes associated with their condition.

6. Family History of Genetic Disorders: If there is a family history of chromosomal abnormalities or genetic disorders, CMA can assess whether the same mutations or anomalies are present in the child.

7. Recurrent Pregnancy Loss: For families who have experienced multiple miscarriages, CMA can detect chromosomal changes that may be contributing to pregnancy losses.
   
   

Advantages of CMA Over Other Postnatal Testing Options

CMA offers several advantages compared to traditional postnatal genetic testing options:

• Higher Resolution: CMA detects chromosomal changes as small as 2.3 kB, offering significantly higher resolution than karyotyping.
• Detection of Copy-Neutral LOH: CMA identifies copy-neutral loss of heterozygosity (Cn-LOH), providing insights into uniparental disomy and autosomal recessive conditions.
• Mosaicism Detection: CMA can detect low-level mosaicism (as low as 20%), which is critical for diagnosing conditions that may only affect specific tissues.
• Comprehensive Coverage: CMA utilizes over 750,000 markers, covering approximately 9,000 genes, with a particular focus on 447 disease-associated genes.

MapmyGenome Offerings

At MapmyGenome, we offer advanced chromosomal microarray testing for postnatal applications, including:

• Chromosomal Microarray Genotyping with Illumina 750K BeadChip: This platform provides high-density cytogenetic analysis optimized for postnatal genetic diagnosis.

• High-Density Screening of 324 Cytogenetic Regions: These regions are commonly associated with known syndromes and are used as hotspots for cytogenetic testing.

• Copy Number Variations as Small as 2.3 kB: Our CMA test detects CNVs and structural variants, providing critical insights into a child‘s genetic makeup.

• Analysis of 495,268 Genomic Structural Variants: This analysis is based on data from the Database of Genomic Variants, allowing for better interpretation of results.

• Detection of Copy-Neutral Loss of Heterozygosity (Cn-LOH): This feature helps screen for uniparental disomy and autosomal recessive disorders, offering additional diagnostic clarity.

• Sex Chromosome and PseudoAutosomal Region Analysis: Our testing includes detailed analysis of sex chromosomes and regions like PAR1 and PAR2, which are important in diagnosing gender-specific genetic conditions.

Test specification

 

Learn more:

Read: Unlock Early Genetic Insights for Better Care

Listen: How CMA Postnatal Testing Transforms Diagnosis

Watch: Breakthroughs in Postnatal CMA for Child Development