A novel and complex chromosomal variation in a child with developmental delay: A case report.

Rationale: Chromosomal variations generate diverse phenotypes, influenced by their size and genomic position. This report presents a previously unreported complex chromosomal rearrangement.

Patient Concerns: An 11-year-old Chinese boy presented with short stature and a decade-long history of growth delay.

Diagnosis: The patient exhibited sinus tachycardia, arrhythmia, hematuria, developmental delay, intellectual disability, and reduced plasma growth hormone levels, alongside chromosomal abnormalities with associated deletions. G-banding analysis revealed a male karyotype (46, XY) with the following structural anomalies: r(1)(p13q32), t(6;21)(q21;q22), der(14)t(1;14)(p13;p12), and der(15)t(1;15)(q32;p12). copy number variation sequencing detected: del(1)(q31.3q32.1).seq[GRCh37/hg19](198,600,001-200,040,000) × 1, del(1)(q32.1).seq[GRCh37/hg19](200,960,001-202,480,000) × 1, del(6)(q14.1).seq[GRCh37/hg19](76,800,001-80,640,000) × 1. The patient's phenotype was attributed to a complex chromosomal rearrangement involving 5 chromosomes, with partial deletions resulting from breakage and rejoining of chromosomes 1 and 6.

Interventions: At age 3, the patient received rehabilitative therapy for developmental delay.

Outcomes: No further treatment was provided following confirmation of the chromosomal abnormalities.

Lessons: This case documents a novel chromosomal rearrangement for the first time, contributing valuable clinical insight and establishing a foundation for future research into related genetic disorders.