Genetic Issues Presenting in the Nursery Flashcards
What is syndrome ..?
syndrome consists of a constellation of anomalies that are often seen together and are due to single underlying cause
e.g., Down’s syndrome due to trisomy 21 or Turner’s syndrome.
What is Associations..?
Associations are clusters of malformations that occur together more frequently than occur sporadically, but their association is not strong enough to classify as a syndrome.
What is Sequence …?
Sequence is defined as a pattern of multiple anomalies derived from a single known or presumed cause, but are embryologically unrelated defects.
It may be a cascade due to mechanical factors—Potter sequence and Pierre Robin sequence.
What is Complex …?
Complex is a multiple system malformation due to a change in the developmental filed (unit).
What is Malformation …?
Malformation is reserved for abnormalities caused by failure or inadequate completion of one or more of the embryonic processes.
An example is neural tube defects caused by failure in the closure of neuropores.
What is Disruptions …?
Disruptions are defects due to extrinsic events that alter structures that have already developed normally.
These events can be due to compromise in circulation, examples - atresia may be due to compromise in gut circulation,
amputation of digits by amniotic band may be due to physical compression.
What are Deformations…?
Deformations can occur when physical forces act on previously formed structures.
Examples of deformations include uterine crowding or oligohydramnios that results in plagiocephaly or clubfeet.
What is Dysplasia …?
Dysplasia refers to abnormal cellular organization or function within a specific tissue type throughout the body resulting in abnormality.
Examples include skeletal dysplasia and ectodermal dysplasia.
What is Noninvasive prenatal screening (NIPS..?
This technique consists of the analysis of cell-free fetal DNA present in the maternal serum.
Massive parallel sequencing of maternal and placental (fetal) fragments of DNA is possible through next-generation sequencing (NGS) platforms
Chromosome studies are typically performed which cells …?
Chromosome studies are typically performed on whole blood drawn into sodium heparin tubes
The T lymphocytes in the blood are stimulated with mitogens, cultured for 72 hours, placed on slides, and karyotype done with banding techniques such as Giemsa trypsin G-banding (GTG)
