A male infant with monosomy 21

Area of Science:

• Genetics
• Human Biology
• Pediatrics

Background:

• Monosomy 21 is a rare chromosomal abnormality with limited documented cases.
• Understanding the phenotypic spectrum of chromosomal disorders is crucial for diagnosis and management.

Purpose of the Study:

• To report a case of total monosomy 21 in a male infant.
• To detail the clinical presentation and genetic findings associated with this condition.

Main Methods:

• Karyotyping using Q-, G-, and R-banding techniques.
• Clinical examination and phenotypic assessment of the infant.

Main Results:

• The infant exhibited total monosomy 21.
• Key symptoms included hypertonia, micrognathia, microphthalmus, imperforate anus, ambiguous genitalia, thumb and finger abnormalities, clubfoot, and growth retardation.
• Both parents were phenotypically and karyotypically normal.

Conclusions:

• This case expands the known clinical spectrum of total monosomy 21.
• The findings highlight the importance of comprehensive genetic analysis in infants with multiple congenital anomalies.