OB week 4

Fetal Anomalies & Syndromes part 1

Questions define malformation. Example? define deformation. types? Example? define disruption. types? Example? define dysplasia. Example? define sequence. Example? define association. Example? define syndrome. Example?

Answers defect of an organ/part that results from an intrinsically (abn from beginning) abnormal developmental process. E.g. cleft lip/palate abnormal form, shape, position of a body part caused by mechanical forces (UT abnormalities, IUGR).  E.g. clubfeet previously normal tissue breaks down as a result of some type of insult to developmental process, not genetic (infection, trauma). E.g. extremity amputation anomaly in which the structure of tissue lacks the normal organization of cells, abn cell development. E.g. congenital ectodermal dysplasia pattern of multiple anomalies that results from an initial single anomaly. E.g. spina bifida, resulting in hydrocephalus and clubfeet nonrandom occurrence in two or more individuals of multiple anomalies not known to be a sequence or syndrome; E.g. VECTRL association pattern of multiple anomalies related to a single cause or pathology; E.g. trisomy 21

Genetics

Questions what are germ cell/gametes responsible for? how many chromosomes do they contain? this is called a ___? how many chromosomes are in a somatic cell? they are called ___? define mitosis. define meiosis. what is a karyotype. what is a female karyotype? male karyotype? 3 types of numeric anomalies? this chromosomal nondisjunction occurs during ___? structural abnormalities are a result of  ___? list 4 types.

Answers production, sperm and egg 23 chromosomes, called a haploid 23 pairs, (22 autosomes and 2 sex chromsomes); called diploid somatic cell replication; 2 daughter cells containing the same genetic information as the original cell germ cell replication; produces 4 daughter cells; can result in structural abnormalities number and appearance of chromosomes in cell female - 46XX, male - 46XY heteroploidy: changes in #chromosomes presentEuploidy: multiples of the haploid number, e.g. triploidy-69chromosomes in the cellaneuploidy: extra/missing chromosome from a set occurs during neiosis result from breakage of chromosome deletion, insertion, inversion, translocation

Questions 4 types of transmission of genetic code? define autosomal dominant transmission. what is the % of a child having that trait? describe autosomal recessive transmission. what is the child's % for having, carrying, or not inheriting the trait? Describe an x-linked transmission. describe multifactorial transmission. what are some risk factors for chromosomal anomalies? what are some types of prenatal screening?

Transmission

Answers transmission: from parents to offspringautosomal dominant, autosomal recessive, X-linked, multifactorial condition ass.c the 22 non-sex chromosomes; child has 50% inheritance  each parent carries the gene; child has 25% chance of condition, 50% chance of becoming carrier ass.c genes located on X chromosome; dominant or recessive both genetic and nongenetic causes; teratogens, infection, drugs, advanced maternal age, ethnicity, prev pregnancy with chromosomal anomalies maternal serum alpha-fetoproteinhCGPAPP-A-preg ass. plasmaNTQuad screen  amniocentesis