Genetic Analysis Strategy for Diagnosing Congenital Heart Disease

Area of Science:

• Genetics
• Cardiology
• Medical Diagnostics

Background:

• Congenital heart defects (CHD) affect 10-12 per 1,000 newborns globally.
• Genetic factors contribute to 20-30% of CHD cases, including copy number variations (CNVs).
• Many CHD patients remain undiagnosed despite genetic testing.

Purpose of the Study:

• To evaluate undiagnosed CHD patients who have undergone genetic testing.
• To provide a diagnostic guideline for resource-limited settings to expedite CHD diagnosis.

Main Methods:

• DNA extraction from CHD patients.
• Analysis using two multiplex ligation-dependent probe amplification (MLPA) kits (P311 for CHD, P245 for microdeletions).
• Prior screening with karyotype and fluorescent in situ hybridization.

Main Results:

• Copy number variations (CNVs) were detected in 36% of the evaluated patients.
• This represents a high detection rate for undiagnosed CHD cases.
• The study highlights the effectiveness of MLPA kits in identifying genetic causes of CHD.

Conclusions:

• Careful patient selection and comprehensive genetic analysis contribute to high detection rates.
• The proposed guideline can facilitate faster and more accurate CHD diagnostics in developing countries.
• Further research can refine diagnostic strategies for complex genetic conditions in CHD.