(Midterm 1 half) Topic 4: Understanding Genotype/Phenotype Interactions

GWAS

Genetic screening tool that searches the genome for haplotype blocks that are more frequent in cases than in controls

Haplotype

A series of alleles found at linked loci that mark recognizable chromosomal segments

linkage disequilibrium, known locus (SNP, polymorphism, etc), non-disease associated allele that segregates with the disease allele

Haplotype are based on _____— sometimes a disease-associated allele in linked to a ______ that marks the ancestral chromosomal segment, therefore we can track ____

Linkage Disequilibrium

A statistical associated between particular alleles at separate but linked loci, normally the result of a particular ancestral haplotype being common in the population studied

LOD Score

Represents the most efficient statistic for evaluating inheritance linkage

evidence for linkage, evidence against linkage

Positive LOD scores show ______ while negative LOD scores show ____

regulatory sequences

Common variants is Autism Spectrum Disorder are associated with haplotype blocks rich in _______, consistent with ASD being considered a neurodevelopmental disorder

Fertilization

The eggs completes meiosis and extrudes the last polar body; pronuclei fuse to create a diploid zygote

Indeterminate Mitosis

Proliferative cell divisions with little to no differentiation; posterior/anterior axis only is determined

Blastula Formation

First real differentiation into the inner cell mass and trophoblast

embryonic tissue, placenta

The inner cell mass becomes the ____ and the trophoblast becomes the ____

Gastrulation

Formation of the germ layers; inner cell mass rearranges by the invagination of a set of cells

Neurulation

Formation of the neural tube (in vertebrates) which occurs anterior to posterior

65-75, known genetic cause, maternal infections and known environmental exposures

___% of birth defects have unknown causes, ~25% can be attributed to a ____, and ~1% can be attributed to _____

fold, elevate, close, fuse, anencephaly, spina bifida

The 4 steps of neurulation are ______. If the neural tube does not fuse at all this is _____ and if the neural tube fails to finish fusing this is _____