Meiotic
Madness
Madness
In meiosis I, this type of chromosomal error results in gametes with both homologous chromosomes from the same parent, leading to conditions such as uniparental disomy.
What is heterodisomy?
This specific chromosomal abnormality occurs when both arms of a chromosome are identical, commonly seen in Turner syndrome.
What is an isochromosome?
This syndrome, resulting from a trisomy 18, presents with overlapping fingers, rocker-bottom feet, and cardiac malformations.
What is Edwards syndrome?
This specific translocation, seen in chronic myelogenous leukemia, leads to the creation of the BCR-ABL fusion geneand results in unchecked tyrosine kinase activity.
What is t(9;22), or the Philadelphia chromosome?
This karyotype represents a normal female with a Robertsonian translocation involving chromosomes 13 and 14.
What is 45,XX,rob(13;14)(q10;q10)?
This specific error during anaphase I or anaphase II leads to aneuploidy, resulting in disorders like trisomy 21.
What is non-disjunction?
This chromosomal rearrangement involves a single chromosome that has lost its telomeric regions and forms a circular structure, often leading to severe phenotypes.
What is a ring chromosome?
This genetic syndrome arises from a deletion at 15q11-q13 on the maternal chromosome and is characterized by intellectual disability, seizures, and a happy demeanor.
What is Angelman syndrome?
This syndrome can result from a Robertsonian translocation involving chromosomes 14 and 21, accounting for a familial form of trisomy 21.
What is familial Down syndrome?
This mosaic karyotype represents a female with a mix of Turner syndrome and normal karyotype cells.
What is 45,X/46,XX?
This mechanism ensures that homologous chromosomes exchange genetic material during meiosis I, creating genetic diversity. Its failure can result in chromosomal abnormalities.
What is meiotic crossover or recombination?
The combination of uniparental disomy and imprinting defects can lead to these two distinct syndromes, depending on whether the maternal or paternal copy of chromosome 15 is deleted.
What are Prader-Willi syndrome and Angelman syndrome?
A newborn presents with polydactyly, cleft palate, and holoprosencephaly. Karyotype shows 47,XY,+13. This syndrome is typically lethal within the first year of life.
What is Patau syndrome?
This aggressive form of non-Hodgkin lymphoma is driven by the translocation t(8;14), which places the MYConcogene next to the immunoglobulin heavy chain gene.
What is Burkitt lymphoma?
This karyotype, 46,XY,del(5)(p14.2), is seen in a syndrome characterized by a distinctive cry in infants.
What is Cri du Chat syndrome?
Non-disjunction in maternal meiosis I is most likely to occur with this particular risk factor, explaining the association of trisomy with increasing maternal age.
What is prolonged oocyte arrest in prophase I?
This cytogenetic abnormality, involving the deletion of the long arm of chromosome 22, is associated with immunodeficiency, conotruncal heart defects, and characteristic facial features.
What is 22q11 deletion syndrome, or DiGeorge syndrome?
This syndrome, associated with short stature, webbed neck, and coarctation of the aorta, results from monosomy X or mosaicism involving the X chromosome.
What is Turner syndrome?
This type of translocation involves two acrocentric chromosomes and results in a karyotype with 45 chromosomes. Though balanced carriers are phenotypically normal, they have a risk of producing unbalanced gametes.
What is a Robertsonian translocation?
A karyotype showing 46,XX,r(21) indicates the presence of this chromosomal abnormality, which involves a circularized chromosome.
What is a ring chromosome 21?
This phenomenon describes the rescue of a trisomic zygote by the loss of an extra chromosome, potentially leading to uniparental disomy in the surviving embryo.
What is trisomic rescue?
This type of chromosomal aberration, commonly seen in cancer, can activate oncogenes by moving them next to highly active gene regions, as seen in Burkitt lymphoma.
What is a reciprocal translocation?
This syndrome, caused by a microdeletion on chromosome 7q11.23, is characterized by an "elfin" facial appearance, cardiovascular defects, and a highly sociable personality.
What is Williams syndrome?
In acute promyelocytic leukemia (APL), this translocation fuses the PML and RARA genes, blocking differentiation at the promyelocyte stage.
What is t(15;17)?
A karyotype with 46,XY,t(9;22)(q34;q11) suggests the presence of this fusion gene, which is a hallmark of chronic myelogenous leukemia.
What is the BCR-ABL fusion gene?