title: Null allele in a human polymorphism restricted to the placenta: call for a search.
abstract: The identification of a null allele in a human genetic system restricted to the placenta is a great challenge for two reasons: the impossibility of carrying out family studies and the unviability of sample recollections because the placenta itself is a disposable universe. Thus, in addition to reporting the finding of a null phenotype of placental alkaline phosphatase in a dark mulatto newborn from a black mixed population of Bahia, Brazil, here we present other evidence for the presence of the ALPP*Q0 allele with considerably high frequency in this population.
authors.affiliation: Departamento de Medicina Preventiva, Universidade Federal da Bahia, Brazil.
authors.forename: M C
authors.initials: MC
authors.lastname: Silva
authors.forename: M G
authors.initials: MG
authors.lastname: Sousa
authors.forename: R D
authors.initials: RD
authors.lastname: Carvalho
authors.forename: M R
authors.initials: MR
authors.lastname: Passos-Bueno
authors.forename: E S
authors.initials: ES
authors.lastname: Azevêdo
mesh_terms: D000469:Alkaline Phosphatase; D000483:Alleles; D001938:Brazil; D005260:Female; D058851:GPI-Linked Proteins; D005787:Gene Frequency; D005828:Genetics, Population; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D007527:Isoenzymes / Q000097:blood / Q000737:chemistry / Q000235:genetics*; D008957:Models, Genetic; D010641:Phenotype; D010920:Placenta / Q000737:chemistry; D011110:Polymorphism, Genetic / Q000235:genetics*; D011247:Pregnancy; D044469:Racial Groups
chemical_list: D058851:GPI-Linked Proteins; D007527:Isoenzymes; D000469:Alkaline Phosphatase; C019839:alkaline phosphatase, placental