Trichorhinophalangeal syndrome type I

Area of Science:

• Genetics and Human Physiology
• Rare Genetic Disorders
• Skeletal Dysplasias

Background:

• Trichorhinophalangeal syndrome (TRPS) is a rare genetic disorder characterized by specific facial features, sparse hair, and skeletal abnormalities.
• TRPS presents in three main types: TRPS I, TRPS II (Langer-Giedion syndrome), and TRPS III, each with distinct clinical manifestations.
• Accurate diagnosis and classification are crucial for understanding the genetic basis and clinical spectrum of TRPS.

Observation:

• A 32-year-old woman presented with short stature, alopecia (hair loss), characteristic facial features (typical facies), and shortened, angulated fingers and toes.
• The patient exhibited features consistent with Trichorhinophalangeal syndrome type I (TRPS I).
• Key diagnostic features, such as the absence of exostosis and mental retardation, helped rule out TRPS II.
• The absence of generalized shortening of all phalanges, metacarpals, and metatarsals distinguished this case from TRPS III.

Findings:

• The reported case is definitively classified as Trichorhinophalangeal syndrome type I (TRPS I) based on the clinical presentation.
• Differential diagnosis excluded TRPS II due to the absence of exostosis and intellectual disability.
• TRPS III was excluded by the lack of generalized shortening across multiple hand and foot bones.

Implications:

• This case reinforces the distinct clinical characteristics that differentiate the subtypes of Trichorhinophalangeal syndrome.
• The findings suggest that the various types of TRPS may stem from genetically identical origins but manifest with a diverse clinical spectrum.
• Further research into the genetic underpinnings of TRPS could elucidate the mechanisms driving this phenotypic variability.