10p duplication characterized by fluorescence in situ hybridization

Area of Science:

• Genetics
• Clinical Medicine
• Developmental Biology

Background:

• Severe failure to thrive and developmental delays are complex conditions often linked to genetic factors.
• Chromosomal abnormalities, including rearrangements and copy number variations, are significant contributors to congenital anomalies and developmental disorders.
• Accurate characterization of chromosomal aberrations is essential for diagnosis and understanding disease mechanisms.

Observation:

• A patient presented with severe failure to thrive, mild-moderate developmental delay, cleft lip and palate, and other anomalies.
• Initial cytogenetic analysis revealed a de novo chromosome rearrangement involving chromosome 4, but the source of the additional material was unclear.
• Detailed analysis using chromosome-specific painting probes defined the karyotype as 46,XY,der(4) t(4;10)(q35;p11.23).

Findings:

• The rearrangement involved a translocation between chromosome 4 and chromosome 10, specifically t(4;10)(q35;p11.23).
• Fluorescence in situ hybridization (FISH) analysis successfully characterized the duplication on the short arm of chromosome 10 (dup(10p)).
• This case highlights a specific type of chromosomal abnormality leading to a complex phenotype.

Implications:

• This case underscores the utility of advanced cytogenetic techniques like FISH in precisely identifying small chromosomal duplications and rearrangements.
• Understanding such genetic variations is critical for accurate diagnosis, genetic counseling, and potential therapeutic strategies in patients with developmental disorders.
• The findings contribute to the growing knowledge base of genotype-phenotype correlations in chromosomal abnormality syndromes.