[Genetic analysis of 46, XX, t(1;6;14) complex translocation: A case report]

Area of Science:

• Human Genetics
• Reproductive Biology
• Cytogenetics

Background:

• Idiopathic primary infertility affects numerous women, often necessitating comprehensive etiological investigations.
• Genetic factors, including chromosomal abnormalities, can significantly impact reproductive outcomes.
• Balanced translocations, while often asymptomatic in carriers, can lead to infertility or recurrent pregnancy loss due to unbalanced gamete formation.

Purpose of the Study:

• To investigate the genetic basis of primary infertility in a 31-year-old female with a history of unexplained infertility.
• To determine the inheritance pattern of a complex chromosomal rearrangement identified in the proband.
• To assess the implications of the identified translocation for familial reproductive risk and genetic counseling.

Main Methods:

• High-resolution G-banding chromosome analysis was performed on the proband.
• Karyotypic analysis was extended to the proband's parents and sister to identify the origin of the rearrangement.
• Nomenclature for the complex three-way translocation was established.

Main Results:

• The proband presented with a balanced three-way translocation: 46, XX, t(1;6;14).
• Her phenotypically normal mother was identified as a carrier of the same balanced translocation, indicating maternal inheritance.
• The proband's father and sister had normal karyotypes.
• The patient's infertility was attributed to the increased risk of producing unbalanced gametes.

Conclusions:

• Conventional karyotype analysis is crucial for diagnosing idiopathic primary infertility, detecting balanced structural rearrangements missed by molecular methods.
• Familial cytogenetic studies are essential for accurate risk assessment and genetic counseling.
• Preimplantation genetic testing (PGT) for structural rearrangements is a key management strategy for carriers seeking to achieve a healthy live birth.