Indications for Constitutional Cytogenetic Investigations

· Peripheral blood:

· Family history:

· Chromosome rearrangement

· Mental retardation of possible chromosomal origin where it is not possible to study the affected individual

· Relative with a history of losses, a malformed fetus, or stillbirth of unknown nature, as clinically indicated

· Recurrent pregnancy losses, stillbirths, or neonatal deaths where it is not possible to study the affected conceptus

· Primary or secondary amenorrhea

· Premature menopause

· Azospermia

· Oligospermia

· Clinically significant abnormal growth

· Short stature

· Excessive growth

· Microcephaly

· Macrocephaly

· Ambiguous genitalia

· Dysmorphism

· Congenital anomalies

· Mental retardation / developmental delay

· Suspected deletion / microdeletion / duplication syndrome

· X-linked recessive condition in a female

· Clinical fefatures of a chromosomal instability syndrome

· Bone marrow transplantation with an opposite ssex donor

· Prenatally diagnosed structural chromosome abnormality or unusual chromosome variant

· Infertility of unknown etiology

· 3 or more pregnancy losses (or 2 or more)

· Clinical features of a syndrome with cytogenetic findings (ex. Roberts, ICF)

· History of unexplained stillbirth or neonatal death

· Fibroblast:

· Clinically suspected mosaicism

· Spontaneous abortions, stillbirths, and infant deaths:

· Unexplained (depending on the policies of the institution)

· With hydrops fetalis, growth restriction, dysmorphic features, anomalies

· Any other condition deemed by a physician as indicating a need for cytogenetic investigation

· Prenatal cytogenetic diagnosis when pathological confirmation is not available

· Mosaic or unusual prenatal cytogenetic diagnosis

· POCs from spontaneous abortion:

· Recurrent spontaneous abortion

· While being treated for another cause of recurrent spontaneous abortion

· Maternal age 35 years or more

· After in vitro fertilization, intracytoplasmic sperm injection, etc

· Pathologic examination suggests possibility of cytogenetic abnormality

·

References:

· CCMG Cytogenetic Practice Guidelines (2003)