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Michael Bamshad

Publications and source records attributed to Michael Bamshad.

7 recordsLinked to original sources

Acro-dermato-ungual-lacrimal-tooth (ADULT) syndrome: report of a child with phenotypic overlap with ulnar-mammary syndrome and a new mutation in TP63.

We report on a new patient with clinical findings consistent with acro-dermato-ungual-lacrimal-tooth (ADULT) syndrome. The child had sparse hair, extensive freckling, lacrimal duct stenosis, oligodontia, dystrophic nails, reduced sweating, and bilateral athelia. Examination of his hands showed ulnar ray hypoplasia with bilateral fifth finger brachydactyly and camptodactyly. He also had surgical repair of an imperforate anus. Mutation analysis of TP63 showed a single nucleotide substitution, c.G518A, predicting a novel missense mutation, p.V114M in exon 4. This is the third mutation to be reported in TP63 in ADULT syndrome.

Abnormalities, Multiple↗

Balinese Y-chromosome perspective on the peopling of Indonesia: genetic contributions from pre-neolithic hunter-gatherers, Austronesian farmers, and Indian traders.

The island of Bali lies near the center of the southern chain of islands in the Indonesian archipelago, which served as a stepping-stone for early migrations of hunter-gatherers to Melanesia and Australia and for more recent migrations of Austronesian farmers from mainland Southeast Asia to the Pacific. Bali is the only Indonesian island with a population that currently practices the Hindu religion and preserves various other Indian cultural, linguistic, and artistic traditions (Lansing 1983). Here, we examine genetic variation on the Y chromosomes of 551 Balinese men to investigate the relative contributions of Austronesian farmers and pre-Neolithic hunter-gatherers to the contemporary Balinese paternal gene pool and to test the hypothesis of recent paternal gene flow from the Indian subcontinent. Seventy-one Y-chromosome binary polymorphisms (single nucleotide polymorphisms, SNPs) and 10 Y-chromosome-linked short tandem repeats (STRs) were genotyped on a sample of 1,989 Y chromosomes from 20 populations representing Indonesia (including Bali), southern China, Southeast Asia, South Asia, the Near East, and Oceania. SNP genotyping revealed 22 Balinese lineages, 3 of which (O-M95, O-M119, and O-M122) account for nearly 83.7% of Balinese Y chromosomes. Phylogeographic analyses suggest that all three major Y-chromosome haplogroups migrated to Bali with the arrival of Austronesian speakers; however, STR diversity patterns associated with these haplogroups are complex and may be explained by multiple waves of Austronesian expansion to Indonesia by different routes. Approximately 2.2% of contemporary Balinese Y chromosomes (i.e., K-M9*, K-M230, and M lineages) may represent the pre-Neolithic component of the Indonesian paternal gene pool. In contrast, eight other haplogroups (e.g., within H, J, L, and R), making up approximately 12% of the Balinese paternal gene pool, appear to have migrated to Bali from India. These results indicate that the Austronesian expansion had a profound effect on the composition of the Balinese paternal gene pool and that cultural transmission from India to Bali was accompanied by substantial levels of gene flow.

Asia, Southeastern↗

Gene flow from the Indian subcontinent to Australia: evidence from the Y chromosome.

Phenotypic similarities between Australian Aboriginal People and some tribes of India were noted by T.H. Huxley during the voyage of the Rattlesnake (1846-1850). Anthropometric studies by Birdsell led to his suggestion that a migratory wave into Australia included populations with affinities to tribal Indians. Genetic evidence for an Indian contribution to the Australian gene pool is contradictory; most studies of autosomal markers have not supported this hypothesis (; and references therein). On the other hand, affinities between Australian Aboriginal People and southern Indians were suggested based on maternally inherited mitochondrial DNA. Here, we show additional DNA evidence in support of Huxley's hypothesis of an Indian-Australian connection using single-nucleotide polymorphisms (SNPs) and short tandem repeats (STRs) on the nonrecombining portion of the Y chromosome (NRY). Phylogenetic analyses of STR variation associated with a major Australian SNP lineage indicated tight clustering with southern Indian/Sri Lankan Y chromosomes. Estimates of the divergence time for these Indian and Australian chromosomes overlap with important changes in the archaeological and linguistic records in Australia. These results provide strong evidence for an influx of Y chromosomes from the Indian subcontinent to Australia that may have occurred during the Holocene.

Archaeology↗

Mixed clefting type in Rapp-Hodgkin syndrome.

Mixed clefting type (MCT) is the rare occurrence of cleft lip, with or without cleft palate, and cleft palate alone in the same pedigree. Here we present a family with Rapp-Hodgkin syndrome (RHS) that manifests MCT, and use this rare finding to suggest that RHS may be related not only to phenotypically similar syndromes, but seemingly dissimilar ones as well. RHS has obvious phenotypic overlap with other ectodermal dysplasia-clefting syndromes (EDCS), such as ectrodactyly-ectodermal dysplasia-clefting syndrome (EEC) and ankyloblepharon-ectodermal dysplasia-clefting syndrome (AEC), all of which show MCT. MCT is also found in the allelic disorders van der Woude syndrome (VDW) and popliteal-pterygium syndrome (PPS). Therefore, while VDW and PPS have little clinical overlap with the EDCS, the common finding of MCT may indicate closer relationships at the developmental or genetic level.

Abnormalities, Multiple↗